KING

Police said tear gas was used because protesters began throwing barricades.

TACOMA - Tacoma Police officers set up barricades at the Port of Tacoma on Saturday afternoon in preparation for another round of anti-war protests.

Nearly 200 protesters gathered Friday night when things got out of hand at about 2:30 a.m.

Home video shows a peaceful demonstration, with people sitting down, singing songs, but then police fired several canisters of tear gas toward the crowd.

A University of Puget Sound student, who was filming the protest, was caught up in the frenzy and started choking from the gas.

"You can't breathe, you feel like your airway's just kind of restricted up, so you're just gasping for air," he said.

One demonstrator said it was just a chaotic scene.

"There was a lot of smoke, a lot of flaming things flying everywhere and the police started marching on the protesters and the protesters  all retreated," he said.

But Tacoma Police say what you don't see in the video is that just before the tear gas canisters were fired, some demonstrators had started  to throw barricades at officers, and the crowd was told to disperse.

"A large number of protesters started to cause a disturbance. They picked up some of these sawhorses and started throwing them in the direction of officers, and then started sitting down to blockade the street." said Det. Brad Graham. "At that point officers had to move in and disperse the crowd."

Anti-war demonstrations have been held at the port since last Saturday.

The 4th Brigade is scheduled to leave for Iraq in April, a month early. On Monday, a deployment ceremony for the unit is planned at Fort Lewis.