A powerful Iranian military commander was killed in a “defensive” airstrike, the U.S. Defense Department said late Thursday.

Qassem Soleimani, head of the Iranian Islamic Revolutionary Guard Corps-Qods Force (IRGC-QF), was actively developing plans to attack U.S. diplomats and service members in Iraq and across the region, the Pentagon said in a statement. President Donald Trump directed the strike, according to the statement. 

“This strike was aimed at deterring future Iranian attack plans,” the statement said.

The attack occurred right outside the Baghdad airport in Iraq, according to multiple media reports. Iranian TV on Friday morning showed photos of Soleimani accompanied by prayers.

Soleimani, who is sanctioned by the United Nations, the European Union and the U.S., was responsible for the deaths of hundreds of American and coalition servicemembers, and the wounding of thousands more, the Pentagon statement said. 

Javad Zarif, the Iranian foreign minister who was sanctioned by the U.S. in July, condemned the strike in a social media post as an “act of international terrorism” and an “extremely dangerous & a foolish escalation.” Zarif said Soleimani was “THE most effective force” against Islamic State of Iraq and al Sham (ISIS), al-Qaida and al-Nusra Front (which is now known as Jabhat Fatah al-Sham).

The strike is sure to escalate tensions between Washington and Tehran. They already have been on heightened alert in the last several days following a breach of the U.S. embassy in Iraq led by Iran-backed militias, including Kata’ib Hizballah, after a U.S. airstrike killed dozens of Iraqis. The militias on Wednesday withdrew from the embassy.

Iran’s top security body will meet Friday to discuss the “criminal” attack that killed Soleimani, its spokesman was quoted as saying by local media, according to a Reuters report.