A Florida protest turned violent Friday, as activists gathered in Jacksonville, New York City, Philadelphia, Newark, Chicago, Detroit, Boston and other cities to demonstrate against the U.S. attack on Syria.

Six people were arrested in Jacksonville ― where up to 200 people were protesting ― after protesters supporting President Donald Trump and demonstrators opposed to the military action turned “riotous” and attacked one another and police in downtown Hemming Plaza, according to the Jacksonville Sheriff’s Office, First Coast News reported.

There was also some tension in Detroit, where more than 30 people protesting Thursday’s U.S. missile strike on the Shayrat Air Base, near Homs, turned out at Grand Martius Park downtown.

At one point they were heckled by some Detroit Tigers fans leaving a game. “Bomb Syria,” shouted one fan, reported MLive.com, though most supporters merely watched.

Unified New York City protesters gathered in midtown at Trump Tower and at Union Square, chanting and holding signs saying “Bombing Syria doesn’t protect people, it kills them,” and “Yes to the refugees, no to the U.S. wars that create them,” NBC reported.

“U.S. intervention has never brought about peace and democracy in other countries,” protester Nina Macapinlac told The New York Daily News. “This farce that by bombing Syria you’re going to be able to bring about democracy is not true.”

crowd gathered in Union Square NYC to protest war in Syria pic.twitter.com/GKjWBssCq6 — marisa kabas (@MarisaKabas) April 7, 2017

Around 100 protesters gathered in Chicago at the Trump Tower there before marching along Michigan Avenue. “Hey, Hey, Donald J, how many kids have you killed today?” chanted demonstrators.

“The tragedy of the children is heart-rending,” protester Vicki Cervantes told WBBM Newsradio. “But I think the response of escalation — of more bombing, of more war — only means more dead children.”

Close to 40 protesters gathered in downtown Philadelphia, with some holding signs reading “Bombs are not the answer.”

Members of a sizeable Syrian Christian community in Allentown, largely supportive of Syria’s President Bashar al-Assad, also planned a rally, CBS News reported.

Organizer Dr. Khaldoun Makhoul, a Syrian who moved to the U.S. 23 years ago, believes the chemical attack that killed 87 people and prompted the U.S. response, occurred when a Syrian rocket struck a chemical weapons arsenal belonging to rebels.

@thephillyvoice's video from a Center City protest against Syria airstrikes Friday pic.twitter.com/sUmXwBsLV3 — Patricia Madej (@PatriciaMadej) April 7, 2017

Syria has reported that seven people were killed and nine injured after the U.S. launched 59 Tomahawk cruise missiles in the first direct American assault on the Syrian regime.

Nikki Haley, the U.S. Ambassador to the United Nations, called the move a “very measured step,” saying the country is prepared to “do more” — but she hopes that “will not be necessary.”

More protests against the missile attack were planned to be held over the weekend.

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