Tensions between the United States and Iran skyrocketed Friday morning after Iran’s Gen. Qasem Soleimani — one of the most powerful figures in the country — was assassinated by a U.S. airstrike approved by President Donald Trump. Iran’s Supreme Leader Ayatollah Ali Kahmeni has vowed “harsh retaliation,” and the U.S. government has urged its citizens to leave the Iraq “immediately” due to the threat of retaliatory attacks against them.

Soleimani was the head of Iran’s elite Quds Force, the foreign arm of the Iranian Revolutionary Guard Corps that backs proxy militias throughout the Middle East — including in Iraq. Soleimani was both the orchestrator and the public face of Iran’s regional maneuvering for decades.

His assassination came after protesters and demonstrators stormed the U.S. Embassy compound in Baghdad on Tuesday, an attack which U.S. officials said was carried out by Iranian-backed militias. The protesters reportedly shouted “Death to America” and planting flags for the Iran-backed militia groups. President Trump deployed roughly 750 U.S. soldiers to the area and condemned Iran for being “fully responsible” for the Embassy compound breach.

In a statement confirming Soleimani’s assassination , the U.S. Department of Defense said the Iranian general “was actively developing plans to attack American diplomats and service members in Iraq and throughout the region,” and had approved the attack on the embassy, seeming to confirm he was killed in retaliation. Speaker of the House Nancy Peolsi condemned the attack for risking escalation, and said that assassination was carried out without an Authorization for the Use of Military Force or the consultation of Congress.

Iran and the U.S. have engaged in escalating moves against each other for over a year now. After President Trump withdrew from the Obama-era Iran Nuclear Deal in 2018 and imposed harsh sanctions on the country, Iran has attacked oil tankers in the region, shot down a U.S. drone, and bombed key Saudi oil facilities.

The Iranian-backed militias’ attack on the U.S. embassy earlier this week was reportedly in response to a series of U.S. airstrikes that killed 25 militia fighters on Sunday. That strike was in turn in retaliation for a rocket strike on an Iraqi military compound that killed a U.S. defense contractor and injured U.S. and Iraqi service members.

Iraq is already in the midst of a tumultuous period of its own . Since October, more than 450 people have been killed in mass protests criticizing the country's poor quality of life and demanding new electoral laws and accountability for corruption. In November, Adel Abdul-Mahdi announced he would resign as Prime Minister of the country after weeks of violent protests.

Here is how events have unfolded in recent days.

Friday, Dec. 27: U.S. defense contractor killed in rocket attack in Iraq

A U.S. defense contractor was killed in an attack on an Iraqi military compound near Kirkuk, Iraq, according to the Associated Press. The attack also injured four U.S. service members and two Iraqi Security Forces members, according to the Department of Defense . As many as 30 rockets were fired in the attack.

The U.S. blamed the Iranian-backed militia for the assault. On Monday, the group denied responsibility for the Dec. 27 attack through a spokesperson, according to the New York Times .

Several other similar attacks have occurred over the past few months, according to AP.

Sunday, Dec. 29: U.S. strikes kill 25 militia members

The U.S. conducts airstrikes on five sites of Kataeb Hezbollah, an Iran-backed militia, according to the Department of Defense . The U.S. indicated that the strikes were in retaliation for the rocket attack. The attack killed 25 fighters, according to the Associated Press.

"The U.S. and its coalition partners fully respect Iraqi sovereignty, and support a strong and independent Iraq. The U.S., however, will not be deterred from exercising its right of self-defense," Assistant to the Secretary of Defense Jonathan Hoffman said in a statement. He called on Iran and the militias to stop attacking U.S. and coalition forces.

The Iraqi government expressed outrage about the attack, calling it a "flagrant violation" of its sovereignty, according to AP.

Monday, Dec. 30: Iraq expresses outrage after airstrike

Speaking to cabinet members, Prime Minister Adel Abdul-Mahdi declared three days of mourning for the people killed in the strikes, according to the Associated Press. He said that he had attempted to stop the U.S. airstrike, but the U.S. had insisted.

Tuesday, Dec. 31: Protesters break into the U.S. Embassy compound

After a funeral for fighters killed in the airstrikes, protesters broke into the U.S. Embassy compound in Baghdad.

Protesters gathered outside the compound shouting “Death to America!” and “Death to Israel!” and started to throw water and stones over its walls. They smashed through a main door, set a reception area on fire, and covered the embassy wall with militia flags and anti-U.S. graffiti. They also planted flags above the reception area, according to the Associated Press. Many were wearing militia uniforms, according to the AP.

The Iraqi security forces didn't try to stop the protesters, permitting them to pass a security checkpoint, according to the AP.

Commanders from militias that support Iran joined the protest outside the embassy, the AP reported.

After the breach, Secretary of Defense Mark T. Esper said in a statement that additional forces are being sent to support the embassy. He also called on Iraq to help protect the facility.

"As in all countries, we rely on host nation forces to assist in the protection of our personnel in country, and we call on the Government of Iraq to fulfill its international responsibilities to do so," Esper said.

U.S. Marines assigned to Special Purpose Marine Air-Ground Task Force-Crisis Response-Central Command deploy to Iraq to bolster security at the US Embassy and ensure the safety of American citizens, Dec. 31. pic.twitter.com/qD84tgKyYI - U.S. Central Command (@CENTCOM) December 31, 2019

President Trump blamed Iran for the contractor's death and the storming of the U.S. Embassy on Twitter.

"They will be held fully responsible," Trump wrote. "In addition, we expect Iraq to use its forces to protect the Embassy, and so notified!"

Iran killed an American contractor, wounding many. We strongly responded, and always will. Now Iran is orchestrating an attack on the U.S. Embassy in Iraq. They will be held fully responsible. In addition, we expect Iraq to use its forces to protect the Embassy, and so notified! - Donald J. Trump (@realDonaldTrump) December 31, 2019

White House press secretary Stephanie Grisham reaffirmed the President's position in a statement to the Associated Press

“As the president said, Iran is orchestrating this attack and they will be held fully responsible,” Grisham said. “It will be the president’s choice how and when we respond to their escalation.”

On Tuesday afternoon, President Trump declared on Twitter that the Embassy is “safe” and that U.S. personnel had rushed to the scene.

The U.S. Embassy in Iraq is, & has been for hours, SAFE! Many of our great Warfighters, together with the most lethal military equipment in the world, was immediately rushed to the site. Thank you to the President & Prime Minister of Iraq for their rapid response upon request.... - Donald J. Trump (@realDonaldTrump) December 31, 2019

Wednesday, January 1: U.S. troops use tear gas and protestors called off

The protests picked up again on Wednesday, as demonstrators started a fire on the roof of the reception area. This prompted U.S. troops to fire tear gas at the crowd, according to the Associated Press and other outlets.

Iraqi federal police, counterterrorism forces and soldiers lined up in between the protesters and the compound. There were no reports of conflict between Iraqi officials and the protesters.

President Donald Trump ordered more troops to be deployed to the Middle East as he asserted that Iran was “fully responsible” for the embassy attack. Approximately 750 troops are expected to be sent as a result of the embassy attack and another 3,000 could possibly be deployed in the next few days.

“This deployment is an appropriate and precautionary action taken in response to increased threat levels against U.S. personnel and facilities, such as we witnessed in Baghdad today,” Defense Secretary Mark Esper said in a written statement, according to the AP.

On Wednesday, leaders in the Popular Mobilization Forces, an umbrella group of state-allied militias, called on demonstrators to end the protest after the Iraqi government asked them to do so, the AP reported.

The militia leaders made it clear to the protesters that “your message has been received.”

"After achieving the intended aim, we pulled out from this place triumphantly," Fadhil al-Gezzi, a militia supporter, told the AP. “We rubbed America's nose in the dirt.”

Many of the tents set up have already been taken down and the protesters have moved away from the Embassy.

Friday, January 3: Iran’s Gen. Qasem Soleimani is assassinated by a U.S. airstrike

In a sharp escalation of the proxy attacks between the U.S. and Iran, Iranian Gen. Qasem Soleimani — the powerful head of Iran’s Quds Force of the Iranian Revolutionary Guards Corps — was assassinated by a U.S. airstrike early Friday morning, the Department of Defense confirmed in a statement. Soleimani was killed near Baghdad’s international airport. Several officials from Iranian-backed Iraqi militias were also killed, according to The New York Times .

“General Soleimani was actively developing plans to attack American diplomats and service members in Iraq and throughout the region,” the Department of Defense said in a statement. “General Soleimani and his Quds Force were responsible for the deaths of hundreds of American and coalition service members and the wounding of thousands more.” The statement adds that Soleimani was behind attacks on U.S. coalition biases in Iraq for the past months, and approved the storming of the U.S. embassy.

Soleimani’s death has put the region — and the larger world — on edge, as allies watch for Iranian retaliation.

The U.S. government has urged U.S. citizens to leave the Iraq “immediately” — either via plane via or via — due to the possibility of retaliation against Americans. U.S. military facilities in the Middle East have heightened security.

The U.S. is also sending around 3,000 more service members to the region, on top of the roughly 5,200 troops already in Iraq, according to the AP. Soleimani’s network of allies is vast, heavily armed and stretches throughout the Middle East, the AP reports.

#Iraq: Due to heightened tensions in Iraq and the region, we urge U.S. citizens to depart Iraq immediately. Due to Iranian-backed militia attacks at the U.S. Embassy compound, all consular operations are suspended. U.S. citizens should not approach the Embassy. pic.twitter.com/rdRce3Qr4a - Travel - State Dept (@TravelGov) January 3, 2020

Iran’s Foreign Minister Javid Zarif tweeted that the strike was an “act of international terrorism,” and said the move was an “extremely dangerous & foolish escalation,” adding that “the US bears responsibility for all consequences of its rouge adventurism.”

The US' act of international terrorism, targeting & assassinating General Soleimani—THE most effective force fighting Daesh (ISIS), Al Nusrah, Al Qaeda et al—is extremely dangerous & a foolish escalation.



The US bears responsibility for all consequences of its rogue adventurism. - Javad Zarif (@JZarif) January 3, 2020

As TIME’s Kark Vick reports, “Soleimani was a major public figure in Iran, a Major General in Iran’s Revolutionary Guards Corps, who was easily the most popular official in an Iranian government that generally is not.” The 62-year-old general was viewed as the mind behind Iran’s strategy throughout the Middle East. Iran state television suspended all programming following Soleimani’s death and displayed a photograph of him along with recitations from the Quran, signally a national tragedy. Soleimani was included in TIME’s 2017 list of the 100 most influential people of the year.

“Soleimani was the international face of resistance,” Iran’s Supreme Leader Ayatollah Ali Khamenei said in a statement, “and all lovers of resistance will be his avengers.” He added that “harsh retaliation is waiting.” Khamenei has ordered three days of public mourning, according to the AP.

According to Bloomberg, the semi-official Iranian Fars news agency reports that Soleimani’s deputy Esmail Ghaani has been named the new commander of Iran’s Quds Force. The AP reports that Iran has already summoned the Swiss charges d’affairs, who represents U.S. interests in Tehran — where there’s been no U.S. embassay since the revolution in the 1970s — to protest the assassination.

Iranian President Hassan Rouhani said the assassination was a “heinous crime" and promised his country would “take revenge,” according to the AP.

Immediately after the attack, President Trump tweeted a single image of an American flag , rather than explictly celebrating the assassination as he did after U.S. forces killed ISIS leader Abu Bakr al-Baghdadi.

But on Friday morning he took to Twitter to defend the killing. “General Qassem Soleimani has killed or badly wounded thousands of Americans over an extended period of time, and was plotting to kill many more...but got caught!,” he wrote. “He was directly and indirectly responsible for the death of millions of people, including the recent large number… of PROTESTERS killed in Iran itself.”

General Qassem Soleimani has killed or badly wounded thousands of Americans over an extended period of time, and was plotting to kill many more...but got caught! He was directly and indirectly responsible for the death of millions of people, including the recent large number.... - Donald J. Trump (@realDonaldTrump) January 3, 2020

Speaking to reporters Friday afternoon, President Trump said that the assassination of Soleimani was to "stop a war." "We did not take action to start a war," he continued. The President added that, "Soleimani has been perpetrating acts of terrors to destabilize the Middle East for the last 20 years. What the United States did yesterday should have been done long ago."

In a statement , Speaker of the House Nancy Pelosi condemned the strike, saying it risks “provoking further dangerous escalation of violence.” She added that the strike was carried out without an Authorization of Use of Military Force or consultation of Congress, and demanded that “the full Congress… be immediately briefed on this serious situation and on the next steps under consideration by the Administration, including the significant escalation of the deployment of additional troops to the region.”

U.S. Secretary of State Mike Pompeo tweeted Friday morning that the “U.S. remains committed to de-escalation.”

Spoke with @HeikoMaas about @realDonaldTrump's decision to take defensive action to eliminate Qassem Soleimani. Germany is also concerned over the Iranian regime’s continued military provocations. The U.S. remains committed to de-escalation. - Secretary Pompeo (@SecPompeo) January 3, 2020

The U.S.’s European allies have supported the move but urged restraint from both parties. The U.S.’s most powerful allies in the Middle East — Israel and Saudi Arabia — meanwhile, may “capitalize on the blow to their joint adversary Iran,” TIME’s Billy Perrigo reports .

Israeli Prime Minister Benjamin Netanyahu returned from a planned trip to Greece after the strike. “President Trump deserves all the credit for acting swiftly, forcefully and decisively,” Netanyahu told reporters before boarding a plane back to Jerusalem. “Israel stands with the United States in its righteous struggle for peace, security and self-defense.” Israel is also likely braced for the possibility of retaliation. Iran’s proxy Hezbollah has over 100,000 rockets in Israel’s neighbor Lebanon.

The attack may also impact the U.S. government’s relationship with the government of Iraq, which is allied with both nations. According the AP, Iraqi Prime Minister Adel Abdul-Mahdi said the assassination was an “aggression against Iraq."

Oil prices have reportedly surged since the attack, amid concerns that instability in the region could impact oil production. Per Aljazeera , dozens of U.S. oil workers are reportedly leaving the country today.

The AP reports thousands of protestors swarmed the streets of Tehran after the Friday Muslim prayers, chanting “Death to deceitful America.”