Weeping amid wails from a crowd of hundreds of thousands of mourners, Iran’s supreme leader on Monday prayed over the remains of a top Iranian general killed in a U.S. airstrike in Baghdad, an attack that’s drastically raised tensions between Tehran and Washington.

The targeted killing of Iranian Revolutionary Guard Gen. Qassem Soleimani already has seen his replacement vow to take revenge. Additionally, Tehran has abandoned the remaining limits of its 2015 nuclear deal with world powers in response to the slaying while in Iraq, the parliament has called for the expulsion of all American troops from Iraqi soil.

The developments could bring Iran closer to building an atomic bomb, set off a proxy or military attack launched by Tehran against America and enable the Islamic State group to stage a comeback in Iraq, making the Middle East a far more dangerous and unstable place.

Adding to the tensions, President Donald Trump threatened to demand billions of dollars in compensation from Iraq or impose “sanctions like they’ve never seen before” if it goes through with expelling U.S. troops.

Soleimani’s daughter, Zeinab, directly threatened an attack on the U.S. military in the Mideast while speaking to a crowd of hundreds of thousands in Tehran that stretched as far as the eye could see. Iranian state TV put the crowd size at “millions,” though that number could not be verified.

“The families of the American soldiers in western Asia … will spend their days waiting for the death of their children,” Zeinab said to cheers.