Kayla Mueller, 26, was taken prisoner in 2013 after she crossed over the Turkish border to visit a hospital in war-ravaged Syria.

The parents of Kayla Mueller, who was raped and tortured by slain ISIS chief Abu Bakr al-Baghdadi, say she could still be alive if Obama had been as decisive as Trump, as they revealed yesterday how they secretly met her captors after her death.

Praising President Donald Trump on Sunday after the announcement of Baghdadi's death, Marsha Mueller told the Arizona Republic: 'I still say Kayla should be here, and if Obama had been as decisive as President Trump, maybe she would have been.'

Meanwhile Carl Mueller, the 26-year-old's father, spoke of his gratitude to General Mark Milley for dedicating the mission to his daughter who died while an ISIS captive in 2015.

Her body was never recovered, but Carl Mueller revealed he and his wife traveled from Arizona to Syria to try to recover her remains and met with an ISIS bride who had kept the American locked up for Baghdadi to sexually abuse.

President Donald Trump praised Mueller as a 'beautiful young woman' on Sunday when he announced the death of the leader of the so-called caliphate, who blew himself up, along with three of his children, during a raid by US special forces.

'We just learned that the whole thing was dedicated to Kayla thanks to General [Mark] Milley and it's very touching,' Carl Mueller told ABC News Sunday.

'President Trump mentioned her today in his statement and he mentioned that he deserved what he got for what he did to Kayla.'

As the world reacted to Baghdadi's death today:

Security was tightened at Syrian prison camps amid fears of riots or revenge attacks following the ISIS leader's death;

Donald Trump said he was considering releasing footage of the special forces raid which cornered Baghdadi at his compound in Syria;

There were hopes that a cache of ISIS material recovered from Baghdadi's compound could reveal the terror group's future plans;

Former Saddam Hussein aide Abdullah Qardash emerged as the terror group's new leader;

Russia offered guarded praise for Trump but insisted that Baghdadi's death had not yet been confirmed;

Turkey hailed Baghdadi's death and boasted that it had co-operated with U.S. forces during the operation in Syria.

Kayla Mueller, an American humanitarian worker, was taken prisoner in 2013 after she crossed over the Turkish border to visit a hospital in war-ravaged Syria.

During her 18-month captivity, Mueller was taken as a wife by Baghdadi and raped multiple times, according to the testimony of Yazidi sex slaves who say they were kept alongside her. She was also forced to convert to Islam but did not truly accept the religion.

Mueller, who was credited for saving the lives of other female captives, was killed in 2015 but her body has never been recovered. After her death was announced in February 2015, her parents journeyed to Irbil to meet with Umm Sayyaf, the wife of high-ranking ISIS oil baron Abu Sayyaf.

Abu Bakr al-Baghdadi, being interviewed by his group's Al-Furqan media outlet, was killed in a US special forces raid in northwestern Syria over the weekend

Satellite image of the residence of the former ISIS leader, Abu Bakr al-Baghdadi in northwestern Syria near the village of Barisha

Security is tightened at ISIS prison camps Security is being tightened at ISIS prisons in Syria amid fears of revenge attacks after the death of the terror group's leader. Kurdish guards are 'on high alert' today as they prepare for possible riots or attacks on the prison camps where thousands of ISIS supporters are held. Baghdadi had urged his followers to break ISIS fanatics out of prison in the last weeks of his life and it is feared he will prove a potent recruiting tool even in death. His demise has not yet been formally announced in the camps but many of the prisoners have phones and the news is likely to have reached them by now. There are also fears that 'sleeper cells' around the world will carry out reprisals and British intelligence chiefs are reportedly stepping up surveillance of extremist suspects today. 'Sleeper cells will seek revenge for Baghdadi's death,' said Mazloum Abdi, the top commander of the Kurdish-led Syrian Democratic Forces (SDF). 'This is why anything is possible, including attacks on prisons,' he said. More than 10,000 ISIS prisoners are being held in Syria while another camp is home to some 70,000 people, mainly relatives of the extremists. Advertisement

Carl Mueller described how 'against the advice of the FBI' they had met Umm Sayyaf, whose husband had previously been killed in a Delta Force strike.

'It makes a big difference when you are talking to these people with a humanitarian attitude,' he told ABC.

'We don't care what you did, what you've done - we just want to know what you know about our daughter to bring her home.

'She was held in many cold, dark places, she was raped by al-Baghdadi, we know that to be a fact ... She was murdered by him or someone in his organization. That's what we're pursuing and that's what we hope that President Trump will help us with.'

The couple said they were still working with President Trump to try to have their daughter's remains repatriated.

'For me what matters most I'm hoping now we will finally get the answers we have been asking for all along ... I think this administration truly might help us. I don’t think they are as closed about what happened,' Marsha Mueller told the Arizona Republic.

Trump announced Sunday morning that Baghdadi 'died like a dog' as the result of a raid on his hideout in northwest Syria.

The president touted the operation and al-Baghdadi's death as 'bigger than bin Laden'. Osama bin Laden, founder of Al-Qaeda and the terrorist leader behind the September 11 terrorist attacks, was killed in 2011 during a Navy SEALs operation during Barack Obama's presidency.

'This is the biggest there is. This is the worst ever. Osama bin Laden was big, but Osama bin Laden became big with the World Trade Center. This is a man who built a whole, as he would like to call it, a country,' Trump said, referencing Baghdadi's creation of the Islamic State.

Trump also referred to Baghdadi and those who followed him as 'losers,' and lauded that no U.S. personnel were lost during the raid. He did say, however, that one 'talented canine' was injured.

'I got to watch much of it. No personnel were lost in the operation, while a large number of Baghdadi's fighters and companions were killed with him,' Trump said during his rare Sunday morning remarks.

'He died after running into a dead-end tunnel, whimpering and crying and screaming all the way,' Trump continued, adding that Baghdadi drug three of his children with him.

'They were led to certain death.

Carl and Marsha Mueller, the parents of Kayla Mueller, who was raped and tortured by slain ISIS chief Abu Bakr al-Baghdadi, say she could still be alive if Obama had been as decisive as Trump

Al-Baghdadi, the leader of the so-called Islamic caliphate, blew himself up during the targeted attack on his lair in Syria's Idlib province in the early hours of Sunday morning. His lair was in a village known for smuggling, and he arrived there 48 hours before the raid

Trump said, without explanation on Saturday that 'Something very big has just happened!' and the White House confirmed the president would be addressing the nation on Sunday morning

Russia offers guarded praise to Trump over Baghdadi raid Russia today gave Donald Trump a muted round of applause for his mission against Abu Bakr al-Baghdadi, but insisted that the ISIS leader's death had yet to be confirmed. Vladimir Putin's spokesman said Trump would have made a 'serious contribution' to fighting ISIS if Baghdadi is indeed dead. 'If this information is confirmed we can talk about a serious contribution by the President of the United States to the fight against international terrorism,' he said. The Russian military had spotted American planes and drones in Syria on Saturday night, Kremlin spokesman Dmitry Peskov told reporters on Monday. But he declined to say whether Russia knew what was happening or had offered any assistance. Trump had voiced his thanks to Russia during his White House statement on Sunday morning. Meanwhile, Turkey today acknowledged it had taken part in the operation and boasted of 'intense' co-ordination with U.S. forces. President Recep Tayyip Erdogan called Baghdadi's death a 'turning point in our joint fight against terrorism'. Saudi Arabia today praised the U.S. operation and said Baghdadi had 'distorted' the reputation of Islam. Advertisement

'He reached the end of the tunnel as our dogs chased him down. He ignited his vest, killing himself and the three children. His body was mutilated by the blast. the tunnel had caved in on it, in addition. But test results gave certain, immediate and totally positive identification. It was him. The thug who tried so hard to intimidate others spent his last moments in utter fear, in total panic and dread, terrified of the American forces bearing down on him,' he said.

Information is now emerging over how the U.S. was able to track down Baghdadi, including details of his whereabouts from two inside informants.

A senior Iraqi intelligence official told the Associated Press that a few months ago an Iraqi aide to al-Baghdadi was killed in western Iraq by a U.S. airstrike, and his wife was arrested and handed over to Iraqi authorities.

The official indicated that the wife ended up being a key source of information on Baghdadi's whereabouts. The Iraqis who had her in custody were ultimately able to pass along to the U.S. coordinates on Baghdadi through information they learned from the aide's wife.

A second Iraqi security official said Baghdadi's brother-in-law was recently arrested by the Iraqis and also gave information on Baghdadi's whereabouts.

The ISIS leader's two wives, who were both wearing explosive devices that never detonated, were taken down. Several of his children were taken from the lair and are still alive. Several others were killed in the attack.

Trump said more people were killed than captured, but confirmed there are some in U.S. custody.

Kurdish-led Syrian Democratic Forces (SDF) confirmed on Sunday they had worked with the U.S. on a 'successful' operation against Islamic State.

'Our strong and effective operations once again confirm our strength and determination to go after (Islamic State),' the head of the SDF's media office said.

Syrians ride a motorcycle past a burnt vehicle near the site where a helicopter gunfire reportedly killed nine people near the northwestern Syrian village of Barisha

Trump considers releasing raid footage Donald Trump said on Monday he may release the footage of the raid that killed Baghdadi amid questions about his description of it. 'We're thinking about it. We may. The question was, am I considering releasing video footage of the raid. And we may take certain parts of it and release it, yes,' the president told reporters at Joint Base Andrews as he prepared to leave for Chicago. Trump watched the special forces operation to kill Baghdadi via drone footage, instead of a body-worn camera. Therefore, he did not see the moment the ISIS leader died, according to military and intelligence officials. Trump had announced in his Sunday press conference that Baghdadi died 'whimpering and crying and screaming', and 'like a dog and a coward'. He described the video footage he watched as 'something really amazing to see' and that it was 'as though you were watching a movie'. Advertisement

The Syrian Democratic Forces is an alliance in the Syrian Civil War made up of primarily Kurdish, Arab and Assyrian/Syriac militias.

SDF General Commander Mazloum Abdi took partial credit for taking down Baghdadi, but also thanked the president and U.S. Army in its efforts, which he said have been under way for almost half-a-year.

'For five months there has been joint intel cooperation on the ground and accurate monitoring, until we achieved a joint operation to kill Abu Bakir al-Baghdadi. Thanks to everybody who participate in this great mission,' Abdi tweeted, tagging Donald Trump's Twitter account.

The president also thanked those who had assisted in finding Baghdadi, participated in the raid and brought him to his death. He said that while the Kurds provided information that was useful in taking down Baghdadi, they did not assist in the military operations.

The ISIS leader has been among U.S. and Europe's force's most wanted figures since his chilling call to arms in 2014, which saw a shift away from the mass casualty attacks carried out by al-Qaeda in favor of smaller-scale acts of violence.

Shifting away from the airline hijackings and other mass-casualty attacks that came to define al-Qaeda, Baghdadi encouraged smaller-scale acts of violence that would be harder for law enforcement to prepare for and prevent.

He encouraged jihadists who could not travel to the caliphate to instead kill where they were using whatever weapon they had at their disposal, resulting in a series of devastating attacks in the UK and Europe.

His words inspired more than 140 terrorist attacks in 29 countries other than Iraq and Syria, resulting in the deaths of at least 2,043 people, CNN reports.

Meeting in the situation room Saturday night (from left to right): National Security Advisor Robert O'Brien, Vice President Mike Pence, Trump, Secretary of Defense Mark Esper and Joint Chiefs of Staff U.S. Army General Mark Milley and Brig. General Marcus Evans

Since 2016, the State Department has offered a reward of up to $25 million for information or intelligence that could lead to Baghdadi's capture or death.

Baghdadi led ISIS for the last five years, presiding over its ascendancy as it cultivated a barbaric reputation for beheadings and horrific executions.

These recordings, often noted for their high production values, were distributed online along with the ISIS propaganda magazine Dabiq.

He remained among the few ISIS commanders still at large despite multiple claims in recent years about his death and even as his so-called caliphate dramatically shrank, with many supporters who joined the cause either imprisoned or jailed.

With a $25 million (£19.5m) bounty on his head, Baghdadi had been far less visible in recent years, releasing only sporadic audio recordings, including one just last month in which he called on members of the extremist group to do all they could to free ISIS detainees and women held in jails and camps.

The Syrian Observatory for Human Rights reported an attack carried out by a squadron of eight helicopters accompanied by a warplane.

The attacks were on positions where ISIS operatives were believed to be hiding in the Barisha area north of Idlib city, after midnight on Saturday-Sunday.

It said the helicopters targeted ISIS positions with heavy strikes for about 120 minutes, during which jihadists targeted the helicopters with heavy weapons.

Reports suggest that al-Baghdadi, the elusive militant who has been the subject of an international manhunt for years, had been killed in Idlib, Syria

The Syrian Observatory documented the death of nine people as a result of the coalition helicopter attack, adding that the death toll is likely to rise due to the presence of a large number of wounded.

The strike came amid concerns that a recent American pullback from northeastern Syria could infuse new strength into the militant group, which had lost vast stretches of territory it had once controlled.

The purported audio was his first public statement since last April, when he appeared in a video for the first time in five years.

In 2014, he was a black-robed figure delivering a sermon from the pulpit of Mosul's Great Mosque of al-Nuri, his only known public appearance.

He urged Muslims around the world to swear allegiance to the caliphate and obey him as its leader.

The death of such a high-value U.S. target comes amid a difficult political backdrop for Trump, who has been frustrated heavy media focus on the Democratic-led impeachment inquiry, which he calls a bipartisan smear.

He has also faced withering criticism from both Republicans and Democrats alike for his U.S. troop withdrawal from northeastern Syria, which permitted Turkey to attack America's Kurdish allies.