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WASHINGTON — Members of Congress said Tuesday night that they were praying for U.S. military forces overseas and that they were monitoring developments following news that Iran launched more than a dozen ballistic missiles at U.S. forces in Iraq.

House Speaker Nancy Pelosi, D-Calif., tweeted that the United States and the world "cannot afford war."

"Closely monitoring the situation following bombings targeting U.S. troops in Iraq. We must ensure the safety of our servicemembers, including ending needless provocations from the Administration and demanding that Iran cease its violence. America & world cannot afford war," she said.

Closely monitoring the situation following bombings targeting U.S. troops in Iraq. We must ensure the safety of our servicemembers, including ending needless provocations from the Administration and demanding that Iran cease its violence. America & world cannot afford war. — Nancy Pelosi (@SpeakerPelosi) January 8, 2020

Vice President Mike Pence briefed Pelosi on the attack, according to her deputy chief of staff, Drew Hammill.

Senate Minority Leader Chuck Schumer, D-N.Y., also got a call from Pence and was briefed at 6:15 p.m., according to a spokesman, who said, "Leader Schumer is closely monitoring the situation & is praying for the safety of our service members & other personnel."

News of the attack came after administration officials briefed congressional leaders in person Tuesday about the U.S. strike that killed Iranian Maj. Gen. Qassem Soleimani. The Defense Department said in a statement Tuesday night that an Iraqi air base housing U.S. forces in Al Anbar province was hit by more than a dozen ballistic missiles from Iran on Wednesday local time.

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House Intelligence Committee Chairman Adam Schiff, D-Calif., was among the so-called Gang of Eight who were briefed. He tweeted Tuesday evening: "With reports of missile strikes launched by Iran against U.S. bases in Iraq, my thoughts and prayers are with our service members, diplomats and other personnel at risk, and with their families."

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Speaking at a rally in Brooklyn, New York, for her presidential campaign, Sen. Elizabeth Warren, D-Mass., said: "My heart and my prayers are with our military and with our families in Iraq and all around the world."

"This is a reminder why we need to de-escalate tension in the Middle East," Warren said. "The American people do not want a war with Iran."

Former Vice President Joe Biden, also a Democratic presidential contender, said it was clear that "chaos" was ensuing in the region because Trump withdrew the United States from the Iran nuclear deal in 2018.

"Some of the things he's done and said in the meantime have been close to ludicrous. Including threatening to bomb holy sites," Biden said.

"And I just pray to God as he goes through what's happening, as we speak, that he's listening to his military commanders for the first time, because so far that has not been the case," he said.

Sen. Rand Paul, R-Ky., a staunch opponent of U.S. intervention overseas who for years has advocated passing a new war powers resolution, said the United States should take action to stop further escalation.

"I am praying for the safety of our troops in Iraq tonight. While I would have preferred they come home long ago, there is also no excuse for this action by Iran. We need to stop the escalation before it leads to another endless war in the Middle East," he tweeted. "In the meantime, the Administration needs to bring any discussion of war with Iran to the American people and their representatives in Congress, as the Constitution requires."

House Foreign Affairs Committee Chairman Eliot Engel, D-N.Y., told NBC News that he hoped Tuesday's attack was not a tit for tat between Trump and Iran.

"The president sometimes thinks that he can sort of stand up and kind of be a tough guy, and then everybody is going to melt," Engel said. "Well, the enemies of the United States are not melting. They're not going anywhere. I think it just makes it more and more difficult to try to end a confrontation like this."

Meanwhile, South Carolina Sen. Lindsey Graham, a close Republican ally of Trump, told Fox News on Tuesday that he spoke to the president earlier in the evening. Calling the strike "an act of war by any reasonable definition," Graham said that "the president has all the authority he needs under Article II to respond."

Full coverage of the standoff with Iran

Sen. James Lankford, R-Okla., tweeted: "Iran's aggression against the US clearly indicates that they continue to want to do harm to Americans & our nation. I am monitoring the situation tonight & I pray for all the servicewomen & men who are defending our nation."

Sen. Jeff Merkley, D-Ore., said everyone should work to prevent a full-fledged war.

"Closely monitoring reports of Iranian missile attacks on military bases housing U.S. military personnel in Iraq. Praying for the safety of our men and women in harm's way," Merkley tweeted. "All of us need to work to break an escalatory cycle to all-out war."

Top administration officials are expected to brief Congress on Wednesday about the situation in Iran and the U.S. decision to kill Soleimani.