WASHINGTON — The U.S. launched large-scale airstrikes on Syria, Defense Secretary Pete Hegseth said Friday, fulfilling President Donald Trump’s vow to strike back after the killing of two U.S. soldiers.

“This is not the beginning of a war — it is a declaration of vengeance,” Hegseth said in a post on X. “Today, we hunted and we killed our enemies. Lots of them. And we will continue.”

The Pentagon referred to Hegseth’s post, while the White House didn’t immediately respond to a request for comment. A spokesperson for U.S. Central Command said the ongoing strikes are targeting ISIS infrastructure and weapon sites.

“All terrorists who are evil enough to attack Americans are hereby warned — YOU WILL BE HIT HARDER THAN YOU HAVE EVER BEEN HIT BEFORE IF YOU, IN ANY WAY, ATTACK OR THREATEN THE U.S.A.,” Trump wrote in a social media post, adding that the Syrian government is “fully in support” of the U.S. operation.

Trump had earlier promised to do “big damage” to the militants behind the deadly attack on American forces in Syria that he blamed on the Islamic State group.

The two U.S. Army soldiers, along with a U.S. interpreter, were killed in the attack last Saturday in the Syrian city of Palmyra during counterterrorism operations.

The gunman was killed, according to U.S. Central Command. Syria’s state-run Sana news agency reported Sunday that security forces arrested five suspects in relation to the attack.

Trump also has taken pains to emphasize the attack was the work of the Islamic State — not Syria’s new government. Palmyra is outside the control of Ahmed al-Sharaa, who has promised to join a U.S.-led coalition to defeat the Islamic State.

During his first term, Trump ordered strikes on Syria twice in a bid to take out Bashar Assad’s chemical weapons program. A strike in April 2017 the U.S. military fired dozens of Tomahawk missiles at an airbase in Syria. A year later, Trump ordered strikes in three facilities linked to the chemical weapons program.

With the strikes on Friday, Trump has now launched major military actions at least three times —against Houthi rebels in Yemen, on Iran’s nuclear program and targeting alleged narcotics-traffickers in the Caribbean Sea and the eastern Pacific Ocean. Separately, his administration has also kept up a counterterrorism campaign against al-Shabab militants in Somalia.

The strikes come about a month after Assad’s successor as president, al-Sharaa, met Trump at the White House and secured additional sanctions relief in exchange for a pledge to join a U.S.-led coalition to defeat Islamic State.

Sharaa’s visit capped a remarkable diplomatic transformation for the former jihadist, who one year ago had a $10 million U.S. bounty on his head. It also marked the first time a Syrian president has visited the White House since the country’s independence in 1946.

(Courtney McBride, Mario Parker and Michelle Jamrisko contributed to this report.)

©2025 Bloomberg L.P. Visit bloomberg.com. Distributed by Tribune Content Agency, LLC.