Iranian forces have launched more than a dozen ballistic missiles against two military bases in Iraq, the Pentagon said Tuesday evening, marking the most significant Iranian attack in the growing conflict with the United States.

The al-Asad air base in western Iraq, which houses some American troops, was hit by at least six rockets about midnight Wednesday, according to a U.S. defense official familiar with the situation.

White House press secretary Stephanie Grisham said officials are aware of reports of attacks on U.S. facilities in Iraq, and added that President Trump was “monitoring the situation closely.”

The strike comes as U.S. officials have defended Trump’s decision to kill Maj. Gen. Qasem Soleimani, the commander of Iran’s elite Quds Force, in an airstrike in Baghdad last week. Iranian leaders stepped up calls Tuesday for revenge against the United States as Iranian authorities prepared to bury Soleimani in his hometown of Kerman, a southeastern city. Early on Tuesday, authorities were forced to suspend the burial proceedings after a stampede killed dozens of mourners.

Here’s what we know so far:

Iranian forces have launched more than a dozen ballistic missiles against two military bases in Iraq.

Secretary of State Mike Pompeo and Defense Secretary Mark T. Esper are at the White House meeting with President Trump following the attack. The President will not make remarks tonight, but the White House may release a statement in response.

● Defense Secretary Mark T. Esper said the United States will not be withdrawing troops from Iraq. The Trump administration is drawing up potential sanctions against Iraq, in the event that its leaders go through with plans to order the expulsion of U.S. troops for Soleimani’s killing on Iraqi soil.

● Iranian state news agencies reported that at least 50 people died and more than 200 were injured in the stampede at the funeral for Soleimani.