A protest over the fatal police shooting of a Guatemalan immigrant turned violent when some demonstrators threw bottles at officers, set trash cans on fire and refused to disperse.

Television news footage showed people tossing the bottles and plastic crates at officers in riot gear late Monday near MacArthur Park, a neighborhood with a large Central American population west of downtown.

Police declared the protest an unlawful assembly around 10 p.m. and ordered the dozens of protesters to disperse. The majority of the crowd cleared out, but a small number lingered and caused trouble, police spokesman Gregory Baek said.

Police arrested and booked four people on suspicion of inciting a riot, which would be a misdemeanor, Officer Bruce Borihanh said. Three officers were bruised but did not require hospitalization and went back on duty, and the confrontation was over by about 2 a.m. Tuesday, he added.

The protest began in the afternoon with demonstrators marching back and forth between a bustling shopping area where the shooting occurred and the Rampart police station three blocks away.

Police said three bicycle officers were patrolling the area Sunday when someone flagged them down and said a man was threatening passers-by with a knife.

When officers confronted the man, they ordered him to drop the knife but he refused, Lt. Andrew Neiman said.

"Instead, he came after the officers with a knife raised in the air, leading one of the officers to fire at the suspect," Neiman said.

Authorities have not released the man's name. However, friends identified him as Manuel Jamines, 37, a construction worker and father of three.

Protesters contend the man was not dangerous and say officers should have used a non-lethal weapon to subdue him.

"When you're trying to stop a suspect or stop a deadly action, the purpose is to stop the threat as quickly as possible," Neiman said.

MacArthur Park was the site of a May 1, 2007, clash, where police officers pummeled immigration rights marchers and reporters with batons and shot rubber bullets into the crowd. Dozens of protesters and journalists were injured as officers cleared the park.

The embarrassing incident cost the city more than $13 million in lawsuit settlements. Police were retrained on crowd control, forming skirmish lines, using batons in a crowd and using extraction teams to identify and arrest violent demonstrators.