Baghdad (CNN) About 75% of the besieged Iraqi city of Tikrit is now back in government control, the head of a key paramilitary force taking part in the attack told CNN on Thursday.

The other 25% is in the hands of about 150 ISIS fighters who continue to hold out, said Main Al-Kadhimi, commander of the Hashd Al-Shaabi militia.

There has been no independent confirmation of such a significant advance by the Iraqi forces. But they have been making progress in recent days.

ISIS' spokesman, Abu Mohammed al Adnani, called reports of coalition-member victories "delusional and fake." He spoke of the coalition's use of fighter jets, heavy artillery and tanks, saying it is a "nightmare and will go eventually."

Children stand next to a burnt vehicle during clashes between Iraqi security forces and ISIS militants in Mosul on Tuesday, June 10.

Children stand next to a burnt vehicle during clashes between Iraqi security forces and ISIS militants in Mosul on Tuesday, June 10.

A Syrian rebel fighter lies on a stretcher at a makeshift hospital in Douma, Syria, on Wednesday, July 9. He was reportedly injured while fighting ISIS militants.

A Syrian rebel fighter lies on a stretcher at a makeshift hospital in Douma, Syria, on Wednesday, July 9. He was reportedly injured while fighting ISIS militants.

Thousands of Yazidi and Christian people flee Mosul on Wednesday, August 6, after the latest wave of ISIS advances.

Thousands of Yazidi and Christian people flee Mosul on Wednesday, August 6, after the latest wave of ISIS advances.

Thousands of Yazidis are escorted to safety by Kurdish Peshmerga forces and a People's Protection Unit in Mosul on Saturday, August 9.

Thousands of Yazidis are escorted to safety by Kurdish Peshmerga forces and a People's Protection Unit in Mosul on Saturday, August 9.

Aziza Hamid, a 15-year-old Iraqi girl, cries for her father while she and some other Yazidi people are flown to safety Monday, August 11, after a dramatic rescue operation at Iraq's Mount Sinjar. A CNN crew was on the flight, which took diapers, milk, water and food to the site where as many as 70,000 people were trapped by ISIS. But only a few of them were able to fly back on the helicopter with the Iraqi Air Force and Kurdish Peshmerga fighters.

Aziza Hamid, a 15-year-old Iraqi girl, cries for her father while she and some other Yazidi people are flown to safety Monday, August 11, after a dramatic rescue operation at Iraq's Mount Sinjar. A CNN crew was on the flight, which took diapers, milk, water and food to the site where as many as 70,000 people were trapped by ISIS. But only a few of them were able to fly back on the helicopter with the Iraqi Air Force and Kurdish Peshmerga fighters.

Kurdish Peshmerga fighters fire at ISIS militant positions from their position on the top of Mount Zardak, east of Mosul, Iraq, on Tuesday, September 9.

Kurdish Peshmerga fighters fire at ISIS militant positions from their position on the top of Mount Zardak, east of Mosul, Iraq, on Tuesday, September 9.

A elderly man is carried after crossing the Syria-Turkey border near Suruc on Saturday, September 20.

A elderly man is carried after crossing the Syria-Turkey border near Suruc on Saturday, September 20.

Syrian Kurds wait near a border crossing in Suruc as they wait to return to their homes in Kobani on Sunday, September 28.

Syrian Kurds wait near a border crossing in Suruc as they wait to return to their homes in Kobani on Sunday, September 28.

A Kurdish Peshmerga soldier who was wounded in a battle with ISIS is wheeled to the Zakho Emergency Hospital in Duhuk, Iraq, on Tuesday, September 30.

A Kurdish Peshmerga soldier who was wounded in a battle with ISIS is wheeled to the Zakho Emergency Hospital in Duhuk, Iraq, on Tuesday, September 30.

Alleged ISIS militants stand next to an ISIS flag atop a hill in Kobani on Monday, October 6.

Alleged ISIS militants stand next to an ISIS flag atop a hill in Kobani on Monday, October 6.

Kiymet Ergun, a Syrian Kurd, celebrates in Mursitpinar, Turkey, after an airstrike by the U.S.-led coalition in Kobani on Monday, October 13.

Kiymet Ergun, a Syrian Kurd, celebrates in Mursitpinar, Turkey, after an airstrike by the U.S.-led coalition in Kobani on Monday, October 13.

Cundi Minaz, a female Kurdish fighter, is buried in a cemetery in the southeastern Turkish town of Suruc on Tuesday, October 14. Minaz was reportedly killed during clashes with ISIS militants in nearby Kobani.

Cundi Minaz, a female Kurdish fighter, is buried in a cemetery in the southeastern Turkish town of Suruc on Tuesday, October 14. Minaz was reportedly killed during clashes with ISIS militants in nearby Kobani.

Heavy smoke rises in Kobani following an airstrike by the U.S.-led coalition on October 18.

Heavy smoke rises in Kobani following an airstrike by the U.S.-led coalition on October 18.

Kurdish fighters walk to positions as they combat ISIS forces in Kobani on Sunday, October 19.

Kurdish fighters walk to positions as they combat ISIS forces in Kobani on Sunday, October 19.

ISIS militants stand near the site of an airstrike near the Turkey-Syria border on Thursday, October 23. The United States and several Arab nations have been bombing ISIS targets in Syria to take out the militant group's ability to command, train and resupply its fighters.

ISIS militants stand near the site of an airstrike near the Turkey-Syria border on Thursday, October 23. The United States and several Arab nations have been bombing ISIS targets in Syria to take out the militant group's ability to command, train and resupply its fighters.

Iraqi special forces search a house in Jurf al-Sakhar, Iraq, on Thursday, October 30, after retaking the area from ISIS.

Iraqi special forces search a house in Jurf al-Sakhar, Iraq, on Thursday, October 30, after retaking the area from ISIS.

A picture taken from Turkey shows smoke rising after ISIS militants fired mortar shells toward an area controlled by Syrian Kurdish fighters near Kobani on Monday, November 3.

A picture taken from Turkey shows smoke rising after ISIS militants fired mortar shells toward an area controlled by Syrian Kurdish fighters near Kobani on Monday, November 3.

Fighters from the Free Syrian Army and the Kurdish People's Protection Units join forces to fight ISIS in Kobani on Wednesday, November 19.

Fighters from the Free Syrian Army and the Kurdish People's Protection Units join forces to fight ISIS in Kobani on Wednesday, November 19.

Smoke billows behind an ISIS sign during an Iraqi military operation to regain control of the town of Sadiyah, about 95 kilometers (60 miles) north of Baghdad, on Tuesday, November 25.

Smoke billows behind an ISIS sign during an Iraqi military operation to regain control of the town of Sadiyah, about 95 kilometers (60 miles) north of Baghdad, on Tuesday, November 25.

An elderly Yazidi man arrives in Kirkuk after being released by ISIS on Saturday, January 17. The militant group released about 200 Yazidis who were held captive for five months in Iraq. Almost all of the freed prisoners were in poor health and bore signs of abuse and neglect, Kurdish officials said.

An elderly Yazidi man arrives in Kirkuk after being released by ISIS on Saturday, January 17. The militant group released about 200 Yazidis who were held captive for five months in Iraq. Almost all of the freed prisoners were in poor health and bore signs of abuse and neglect, Kurdish officials said.

ISIS militants are seen through a rifle's scope during clashes with Peshmerga fighters in Mosul, Iraq, on Wednesday, January 21.

ISIS militants are seen through a rifle's scope during clashes with Peshmerga fighters in Mosul, Iraq, on Wednesday, January 21.

Junko Ishido, mother of Japanese journalist Kenji Goto, reacts during a news conference in Tokyo on Friday, January 23. ISIS would later kill Goto and another Japanese hostage, Haruna Yukawa.

Junko Ishido, mother of Japanese journalist Kenji Goto, reacts during a news conference in Tokyo on Friday, January 23. ISIS would later kill Goto and another Japanese hostage, Haruna Yukawa.

Collapsed buildings are seen in Kobani on January 27 after Kurdish forces took control of the town from ISIS.

Collapsed buildings are seen in Kobani on January 27 after Kurdish forces took control of the town from ISIS.

Kurdish people celebrate in Suruc, Turkey, near the Turkish-Syrian border, after ISIS militants were expelled from Kobani on Tuesday, January 27.

Kurdish people celebrate in Suruc, Turkey, near the Turkish-Syrian border, after ISIS militants were expelled from Kobani on Tuesday, January 27.

A Kurdish marksman looks over a destroyed area of Kobani on Friday, January 30, after the city had been liberated from the ISIS militant group. The Syrian city, also known as Ayn al-Arab, had been under assault by ISIS since mid-September.

A Kurdish marksman looks over a destroyed area of Kobani on Friday, January 30, after the city had been liberated from the ISIS militant group. The Syrian city, also known as Ayn al-Arab, had been under assault by ISIS since mid-September.

Safi al-Kasasbeh, right, receives condolences from tribal leaders at his home village near Karak, Jordan, on Wednesday, February 4. Al-Kasasbeh's son, Jordanian pilot Moath al-Kasasbeh, was burned alive in a video that was recently released by ISIS militants. Jordan is one of a handful of Middle Eastern nations taking part in the U.S.-led military coalition against ISIS.

Displaced Assyrian women who fled their homes due to ISIS attacks pray at a church on the outskirts of Damascus, Syria, on Sunday, March 1. ISIS militants abducted at least 220 Assyrians in Syria.

Displaced Assyrian women who fled their homes due to ISIS attacks pray at a church on the outskirts of Damascus, Syria, on Sunday, March 1. ISIS militants abducted at least 220 Assyrians in Syria.

Iraqi Shiite fighters cover their ears as a rocket is launched during a clash with ISIS militants in the town of Al-Alam, Iraq, on Monday, March 9.

Iraqi Shiite fighters cover their ears as a rocket is launched during a clash with ISIS militants in the town of Al-Alam, Iraq, on Monday, March 9.

The parents of 19-year-old Mohammed Musallam react at the family's home in the East Jerusalem Jewish settlement of Neve Yaakov on Tuesday, March 10. ISIS released a video purportedly showing a young boy executing Musallam, an Israeli citizen of Palestinian descent who ISIS claimed infiltrated the group in Syria to spy for the Jewish state. Musallam's family told CNN that he had no ties with the Mossad, Israel's spy agency, and had, in fact, been recruited by ISIS.

On April 1, Shiite militiamen celebrate the retaking of Tikrit, which had been under ISIS control since June. The push into Tikrit came days after U.S.-led airstrikes targeted ISIS bases around the city.

On April 1, Shiite militiamen celebrate the retaking of Tikrit, which had been under ISIS control since June. The push into Tikrit came days after U.S.-led airstrikes targeted ISIS bases around the city.

People in Tikrit inspect what used to be a palace of former President Saddam Hussein on April 3.

People in Tikrit inspect what used to be a palace of former President Saddam Hussein on April 3.

A Yazidi woman mourns for the death of her husband and children by ISIS after being released south of Kirkuk on April 8. ISIS is known for killing dozens of people at a time and carrying out public executions, crucifixions and other acts.

A Yazidi woman mourns for the death of her husband and children by ISIS after being released south of Kirkuk on April 8. ISIS is known for killing dozens of people at a time and carrying out public executions, crucifixions and other acts.

Kurdish Peshmerga forces help Yazidis as they arrive at a medical center in Altun Kupri, Iraq, on April 8.

Kurdish Peshmerga forces help Yazidis as they arrive at a medical center in Altun Kupri, Iraq, on April 8.

Yazidis embrace after being released by ISIS south of Kirkuk, Iraq, on Wednesday, April 8. ISIS released more than 200 Yazidis , a minority group whose members were killed, captured and displaced when the Islamist terror organization overtook their towns in northern Iraq last summer, officials said.

Thousands of Iraqis cross a bridge over the Euphrates River to Baghdad as they flee Ramadi on Friday, April 17.

Thousands of Iraqis cross a bridge over the Euphrates River to Baghdad as they flee Ramadi on Friday, April 17.

A member of Afghanistan's security forces stands at the site where a suicide bomber on a motorbike blew himself up in front of the Kabul Bank in Jalalabad, Afghanistan, on Saturday, April 18. ISIS claimed responsibility for the attack. The explosion killed at least 33 people and injured more than 100 others, a public health spokesman said.

A member of Afghanistan's security forces stands at the site where a suicide bomber on a motorbike blew himself up in front of the Kabul Bank in Jalalabad, Afghanistan, on Saturday, April 18. ISIS claimed responsibility for the attack. The explosion killed at least 33 people and injured more than 100 others, a public health spokesman said.

Iraqi soldiers fire their weapons toward ISIS group positions in the Garma district, west of the Iraqi capital of Baghdad, on Sunday, April 26. Pro-government forces said they had recently made advances on areas held by Islamist jihadists.

Iraqi soldiers fire their weapons toward ISIS group positions in the Garma district, west of the Iraqi capital of Baghdad, on Sunday, April 26. Pro-government forces said they had recently made advances on areas held by Islamist jihadists.

People search through debris after an explosion at a Shiite mosque in Qatif, Saudi Arabia, on Friday, May 22. ISIS claimed responsibility for the attack, according to tweets from ISIS supporters, which included a formal statement from ISIS detailing the operation.

Residents examine a damaged mosque after an Iraqi Air Force bombing in the ISIS-seized city of Falluja, Iraq, on Sunday, May 31. At least six were killed and nine others wounded during the bombing.

Residents examine a damaged mosque after an Iraqi Air Force bombing in the ISIS-seized city of Falluja, Iraq, on Sunday, May 31. At least six were killed and nine others wounded during the bombing.

Syrians wait near the Turkish border during clashes between ISIS and Kurdish armed groups in Kobani, Syria, on Thursday, June 25. The photo was taken in Sanliurfa, Turkey. ISIS militants disguised as Kurdish security forces infiltrated Kobani on Thursday and killed "many civilians," said a spokesman for the Kurds in Kobani.

Syrians wait near the Turkish border during clashes between ISIS and Kurdish armed groups in Kobani, Syria, on Thursday, June 25. The photo was taken in Sanliurfa, Turkey. ISIS militants disguised as Kurdish security forces infiltrated Kobani on Thursday and killed "many civilians," said a spokesman for the Kurds in Kobani.

People in Ashmoun, Egypt, carry the coffin for 1st Lt. Mohammed Ashraf, who was killed when the ISIS militant group attacked Egyptian military checkpoints on Wednesday, July 1. At least 17 soldiers were reportedly killed, and 30 were injured.

Protesters in Istanbul carry anti-ISIS banners and flags to show support for victims of the Suruc suicide blast during a demonstration on Monday, July 20.

Protesters in Istanbul carry anti-ISIS banners and flags to show support for victims of the Suruc suicide blast during a demonstration on Monday, July 20.

Mourners in Gaziantep, Turkey, grieve over a coffin Tuesday, July 21, during a funeral ceremony for the victims of a suspected ISIS suicide bomb attack. That bombing killed at least 31 people in Suruc, a Turkish town that borders Syria. Turkish authorities blamed ISIS for the attack.

Saudi officials and investigators check the inside of the mosque on August 6.

Saudi officials and investigators check the inside of the mosque on August 6.

The governor of the Asir region in Saudi Arabia, Prince Faisal bin Khaled bin Abdulaziz, left, visits a man who was wounded in a suicide bombing attack on a mosque in Abha, Saudi Arabia, on August 6. ISIS claimed responsibility for the explosion, which killed at least 13 people and injured nine others.

Buildings reduced to piles of debris can be seen in the eastern suburbs of Ramadi on August 6.

Buildings reduced to piles of debris can be seen in the eastern suburbs of Ramadi on August 6.

Smoke rises as Iraqi security forces bomb ISIS positions in the eastern suburbs of Ramadi, Iraq, on August 6.

Smoke rises as Iraqi security forces bomb ISIS positions in the eastern suburbs of Ramadi, Iraq, on August 6.

An ISIS fighter poses with spoils purportedly taken after capturing the Syrian town of al-Qaryatayn.

An ISIS fighter poses with spoils purportedly taken after capturing the Syrian town of al-Qaryatayn.

In this image taken from social media, an ISIS fighter holds the group's flag after the militant group overran the Syrian town of al-Qaryatayn on Thursday, August 6, the London-based Syrian Observatory for Human Rights reported. ISIS uses modern tools such as social media to promote reactionary politics and religious fundamentalism. Fighters are destroying holy sites and valuable antiquities even as their leaders propagate a return to the early days of Islam.

Iraqi men look at damage following a bomb explosion that targeted a vegetable market in Baghdad on Thursday, August 13. ISIS claimed responsibility for the attack.

Iraqi men look at damage following a bomb explosion that targeted a vegetable market in Baghdad on Thursday, August 13. ISIS claimed responsibility for the attack.

Smoke rises above a damaged building in Ramadi, Iraq, following a coalition airstrike against ISIS positions on Saturday, August 15.

Smoke rises above a damaged building in Ramadi, Iraq, following a coalition airstrike against ISIS positions on Saturday, August 15.

Shiite fighters, fighting alongside Iraqi government forces, fire a rocket at ISIS militants as they advance toward the center of Baiji, Iraq, on Monday, October 19.

Shiite fighters, fighting alongside Iraqi government forces, fire a rocket at ISIS militants as they advance toward the center of Baiji, Iraq, on Monday, October 19.

Members of the Egyptian military approach the wreckage of a Russian passenger plane Sunday, November 1, in Hassana, Egypt. The plane crashed the day before, killing all 224 people on board. ISIS claimed responsibility for downing the plane, but the group's claim wasn't immediately verified.

Syrian government troops walk inside the Kweiras air base on Wednesday, November 11, after they broke a siege imposed by ISIS militants.

Syrian government troops walk inside the Kweiras air base on Wednesday, November 11, after they broke a siege imposed by ISIS militants.

Smoke rises over the northern Iraqi town of Sinjar on November 12. Kurdish Iraqi fighters, backed by a U.S.-led air campaign, retook the strategic town, which ISIS militants overran last year. ISIS wants to create an Islamic state across Sunni areas of Iraq and Syria.

Emergency personnel and civilians gather at the site of a twin suicide bombing in Beirut, Lebanon, on Thursday, November 12. The bombings killed at least 43 people and wounded more than 200 more. ISIS appeared to claim responsibility in a statement posted on social media.

Wounded people are helped outside the Bataclan concert hall in Paris following a series of coordinated attacks in the city on Friday, November 13. The militant group ISIS claimed responsibility for the attacks, which killed at least 130 people and wounded hundreds more.

Investigators check the scene of a mosque attack Friday, November 27, in northern Bangladesh's Bogra district. ISIS has claimed responsibility for the attack that left at least one person dead and three more wounded.

Yemenis check the scene of a car bomb attack Sunday, December 6, in Aden, Yemen. Aden Gov. Jaafar Saad and six bodyguards died in the attack , for which the terror group ISIS claimed responsibility.

Syrian pro-government forces gather at the site of a deadly triple bombing Sunday, January 31, in the Damascus suburb of Sayeda Zeynab . ISIS claimed responsibility for the attack, according to a statement circulating online from supporters of the terrorist group.

Syrians gather at the site of a double car bomb attack in the Al-Zahraa neighborhood of the Homs, Syria, on February 21, 2016. Multiple attacks in Homs and southern Damascus kill at least 122 and injure scores, according to the state-run SANA news agency. ISIS claimed responsibility.

Wounded passengers are treated following a suicide bombing at the Brussels Airport on March 22, 2016. The attacks on the airport and a subway killed 32 people and wounded more than 300. ISIS claims its "fighters" launched the attacks in the Belgian capital.

On Wednesday, joint Iraqi forces gained control of Tikrit Military Hospital, a few blocks south of the presidential palace. It's part of their ongoing quest to wrest control from ISIS, which captured the city last year.

The predominantly Shiite militia has been working with Iraqi troops as well as Sunni fighters to try to regain Tikrit.

Tikrit, best known to Westerners as the birthplace of former Iraqi dictator Saddam Hussein , fell in June to ISIS, which has captured large areas of Iraq and Syria for what it says is its Islamic caliphate.

On March 1, Iraqi Prime Minister Haider al-Abadi ordered Iraqi forces to retake Tikrit and Salaheddin province.

ISIS wasn't making it easy, however. The Sunni extremist group blew up a key bridge near Tikrit, preventing the joint Iraqi forces from using it to cross the Tigris River to approach the city from the east.

Nevertheless, forces have made progress, forcing ISIS fighters to retreat toward the city center from front-line positions, Hashd Al-Shaabi's media office said.

Iranian support

There have been several failed attempts to recapture Tikrit since the second half of 2014. If Iraq regains control of the city, it could mean that retaking Mosul -- a city 10 times bigger -- is possible.

The Tikrit offensive involves around 30,000 fighters.

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Gen. Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff, told a hearing of the Senate Foreign Relations Committee on Wednesday that the consensus was that Iran's involvement was positive in military terms. "Anything anyone does to counter ISIS is in the main a good outcome," he said.

But Dempsey also voiced concern over what might happen after ISIS is defeated. A key question, he said, is "whether the government of Iraq will remain on a path to provide an inclusive government for all of the groups" in Iraq.

Tikrit could act as an important testing ground, with some observers concerned that if the predominantly Shiite militias seize control, thanks in part to the support of majority-Shiite Iran, they could carry out reprisal attacks against the remaining Sunni population there.

Such attacks could inflame already simmering sectarian tensions within Iraq and make future efforts to retake Mosul and bring peace to the country yet more difficult.

In a possible sign of the problems to come, a number of posts on social media appear to show Iraqi soldiers in extremely graphic "selfies" with the heads of alleged ISIS militants, or striking odd poses with bodies behind them.

Most of the photos are thought to have been taken during the Iraqi military offensive to retake Tikrit and other areas in Salaheddin province, which started 10 days ago.

Two senior security officials in Samarra told CNN, on condition of anonymity because they are not authorized to speak to media, that they are looking into these claims and they are also investigating similar incidents. They did not confirm or deny the authenticity of the images.

Sectarian division

Anthony Cordesman, a security expert at the Center for Strategic and International Studies, said sectarian division was an issue to be "extremely concerned" about as Iraqi forces gain ground in Tikrit.

"It's already been very clear to Iraqis that this is an Iranian-led operation and not one which has the support of the coalition," he said. As some Iraqis question why the United States has not taken more decisive action, he said, "this may be a case where Iran may be gaining very serious influence."

If there are reprisals in Tikrit and it becomes a "Shiite-on-Sunni struggle," Cordesman said, then not only will Iran's influence increase "but you can see the country divide and Islamic State (ISIS) be replaced by a conflict between Iraqi Shiite and Sunni."

Strong leadership will be needed from the government in Baghdad, headed by al-Abadi, militia leaders and senior religious figures to prevent this outcome, he said, with a lot already being done on this front.

The top Iraqi Shiite cleric, Grand Ayatollah Ali al-Sistani, he said, "very clearly says that Iraqis must act as Iraqis, not divide along sectarian lines."

The challenge will be ensuring that fighters on the ground, some angered by the killings of their relatives by ISIS, do not seek vengeance against Sunni communities whom they suspect of supporting the group.

Ramadi under fierce assault by ISIS

While Iraqi forces piled the pressure on ISIS in Tikrit, the Sunni extremist group continued to flex its muscles in Iraq's western Anbar province, where it is finding a support base among the predominantly Sunni population.

More than 40 Iraqi soldiers were killed when ISIS blew up the Iraqi army headquarters just outside Ramadi, an Anbar provincial leader told CNN on Thursday. Militants dug a tunnel and detonated hundreds of homemade explosives, said Sabah Al-Karhout, head of the Anbar Provincial Council.

ISIS launched a new offensive on Ramadi, west of Baghdad, on Wednesday morning, Faleh al-Issawi, the deputy head of the council, said in a statement.

The city is being attacked "from all directions," with ISIS firing more than 150 mortar rounds and rockets, he said, and explosives-laden vehicles used to attack security checkpoints and a bridge.

Officials believe "this is an ISIS response to the Tikrit operation that is ongoing in the north," al-Issawi said.

U.S.-led coalition forces carried out 13 airstrikes in Iraq between Wednesday and Thursday morning, a statement said. Five hit ISIS targets near Kirkuk, and three struck ISIS units and a vehicle near Falluja.

Battle for Karma

Elsewhere in Anbar province, Iraqi security forces have managed to wrest back most of the town of Karma, near Falluja, from ISIS, said Sabah Al-Karhout, the head of the Anbar Provincial Council, on Wednesday.

Iraqi security forces were fighting side by side with Shiite Hashd Al-Shaabi units and local tribesmen, Al-Karhout said.

ISIS is also battling in many places far from Tikrit, including Syria, where the militant group is more on the offensive, according to the Syrian Observatory for Human Rights, a London-based monitoring group.

Clashes continued Thursday between the Kurdish People's Protection Units, or Kurdish YPG, and ISIS fighters in Ras al Ayn, a Syrian strategic border town with Turkey, the Syrian Observatory said in a statement.

Hundreds of ISIS militants launched a large-scale offensive Wednesday in the town, the group said. Dozens have been killed from both sides.