In an address to the nation from the White House on Wednesday morning, President Trump said no Americans were killed or wounded when Iranian forces launched more than a dozen ballistic missiles against two military bases in Iraq early Wednesday local time, marking the most significant Iranian attack in a growing conflict with the United States.

Defense Secretary Mark T. Esper said Wednesday evening that Iran launched 16 ballistic missiles, including 11 that landed at al-Asad air base and one in Irbil.

Speaking to reporters at the Pentagon, Esper said the missiles struck tents, a helicopter and other items but did not cause major damage.

Gen. Mark A. Milley, chairman of the Joint Chiefs of Staff, told reporters that he thinks Iranian forces intended to kill Americans and cause destruction but that an intelligence assessment would continue.

U.S. officials said Wednesday that they knew Iranian missiles were coming hours in advance of the attack after warnings from intelligence sources and communications from Iraq. Iraq’s acting prime minister has said he was informed of the attack ahead of time.

“We knew, and the Iraqis told us, that this was coming many hours in advance,” said a senior U.S. administration official who spoke on the condition of anonymity due to the sensitivity of the communications.

Speaker Nancy Pelosi (D-Calif.) announced that the House will vote Thursday on a measure to limit Trump’s military actions regarding Iran. Sen. Mike Lee (R-Utah) said the classified briefing by Trump administration officials Wednesday was “probably the worst briefing I’ve seen at least on a military issue in the nine years I’ve served in the United States Senate.”

Here’s what we know so far:

● The U.S. military said no Americans were killed or wounded in the Iranian missile attacks on bases in Iraq early Wednesday.

● U.S. officials said they knew Iranian missiles were coming hours before the attack.

● Iran’s supreme leader, Ayatollah Ali Khamenei, called the attack a “slap in the face” of the United States but said more needed to be done to end the U.S. presence in the region and avenge the death of powerful Iranian military commander Qasem Soleimani.

● Iraq’s acting prime minister said he was informed of the attack ahead of time.

● Lawmakers left a closed-door briefing with top national security officials divided over whether the strike that killed Soleimani was legally justified, and Pelosi said the House will vote Thursday on a measure to limit Trump’s military actions regarding Iran.