In rainy and gray conditions, anti-war protesters gathered in downtown Boston Saturday afternoon in response to the killing of Iranian Maj. Gen. Qassem Soleimani.

"It is time to mobilize our fellow citizens and residents of this country, to take up action, to do all we can now to prevent what is heading toward a very disastrous war," said Paul Shannon, speaking to demonstrators at the rally outside the Park Street MBTA station.

Critics of President Donald Trump’s decision to authorize the killing of Iran’s top general held protests across the state on Saturday.

Massachusetts Peace Action, a group that identifies itself as a grassroots peace and disarmament membership organization, said it opposes war with Iran and criticizes the U.S. killing of Soleimani, calling it an illegal action taken without consulting Congress. The group helped organize the protests around the state.

Cole Harrison, the group’s executive director, said war with Iran would fail to achieve any of its aims, launch an entire region into a conflict and bring about civilian suffering.

Harrison said before the rally that protesters were gathering to demand presidential candidates and members of Congress speak out on the crisis, and that Congress take urgent action.

Members of Massachusetts’ all-Democratic congressional delegation have called on Trump to brief lawmakers on his decision to authorize the killing of Soleimani.

Trump said in a tweet Friday that he ordered the killing of Soleimani because he was “plotting to kill” many Americans and that “he should have been taken out many years ago.”

At the Boston protest, demonstrators held signs asking for peace, decrying a war with Iran, and demanding that the U.S. leave the Middle East region.

"If Iran openly assassinated a top U.S. general and bragged about it, there would be no question the United States would initiate a full-scale war," Nino Brown, a speaker for the ANSWER Coalition, said at the rally. "Trump and the Pentagon have acted illegally."

Mojgan Haji, an Iranian-American, attended the protest and said she worries about a potential war. She said her 86-year-old father and other family members still live in Iran.

"... It's not just about my family, it's about people. It's about people here. It's about people in Iran," Haji said. "And nobody wins in this war except defense contractors."