Early on Friday, a U.S. airstrike in Iraq killed Qassem Soleimani, an Iranian general and prominent member of the government.

The Associated Press reports that the U.S. Department of Defense believed Soleimani was “actively developing plans to attack American diplomats and service members in Iraq and throughout the region.”

Supreme Leader Ayatollah Ali Khamenei informed the American government that a “harsh retaliation is waiting.” Six other people were the victims of the American attack.

Here is how members of Colorado’s congressional delegation responded:

“I think this was a terribly reckless and provocative act. It’s the latest in a long string of non-strategic choices that Donald Trump has made in the Middle East, that has weakened our position in the Middle East, that has strengthened Iran’s position in the Middle East. And I think you couldn’t be more naive to believe that this was going to result somehow in Iran coming to the negotiating table, rather than creating the potential for another war — which is the last thing we need in the Middle East.” — U.S. Sen. Michael Bennet

“I commend the Administration for taking this decisive action today in Baghdad against Tehran-backed terrorists. The world should not mourn Qassem Soleimani, a man whose name is synonymous with murder in the Middle East and who was responsible for the deaths of hundreds of American service members. I now urge the Administration to be prepared for possible retaliation, including against U.S. troops stationed in the region, and to consult closely with Congress on any next steps should the situation escalate. I hope Iran will realize its future depends on stopping its support of terrorism.” — U.S. Sen. Cory Gardner

“I’m deeply concerned by the escalation of violence with Iran that occurred overnight. Congress has the sole constitutional authority to declare war. And while Iran continues to pose a serious threat to our nation’s security, and our interests abroad, no one wants to see America drawn back into a decades-long war in the Middle East … . Congress must be briefed immediately on this situation. We need to know exactly why the administration authorized this attack, and how it plans to protect Americans at home and abroad from its aftermath.” — U.S. Rep. Diana DeGette

“Only Congress has the power to declare war. The President’s unilateral decision to launch this airstrike, yet again, comes without consultation or caution and signals the need for clarification of the Authorization of Military Force … . Congress must reassert its constitutional obligations under Article I without further delay.” — U.S. Rep. Joe Neguse

“We will not will not tolerate attacks on our citizens by murderous terrorists. I applaud the administration’s swift action to take Soleimani out, the world will be safer without him.” —U.S. Rep. Scott Tipton, via Twitter

“I am pleased to hear that @realDonaldTrump and @SecPompeo took action against the brutal terrorist, Qassem Soleimani. He had the blood of hundreds of our brave American warriors on his hands & orchestrated attacks on coalition bases — including the U.S. Embassy in Baghdad.” — U.S. Rep. Doug Lamborn via Twitter

“The question is not whether Qasem Soleimani was a threat to the United States, the question is whether President Trump has a strategy in place to deal with the potentially seismic events that he has unleashed. My time serving as a paratrooper in Iraq taught me that using force without a strategy and clearly defined goals rarely ends well … . The President must explain his policy towards Iran and give the American people confidence that we have a coherent strategy for protecting our embassies, our troops, and our national security.” —U.S. Rep. Jason Crow