SAN FRANCISCO -- A moving protest calling for the disbanding of the BART police force after an officer shot and killed a homeless man last week forced major delays for three hours and the closure of three stations during the Monday evening rush hour.

All service was back to normal by dusk.

The protest started at 5 p.m. at the Civic Center station and within 30 minutes BART had closed the station and trains rolled through without stopping. BART passengers and protesters walked the Powell Street station, but found the turnstiles locked for about 20 minutes.

People were angry, frustrated, confused and unsure of how to proceed.

"It's almost been an hour. I'm trying to get home," said Rasheda Broussard, of San Francisco, while waiting at the Powell Street station. "I don't understand why they let the protesters even get on the trains."

Some protesters stayed quiet and waited with commuters at the Powell Street station turnstiles until they opened, then began screaming "cops, pigs, murderers" and "no justice, no peace, disband the BART police," on the platform. A handful of BART police lined up shoulder to shoulder and waited, expressionless, until the protesters hopped a Millbrae-bound train. Protesters also fanned out to the 16th Street station, which was closed temporarily but reopened by nightfall.

The group, a mix of young and old, distributed fliers to BART passengers, explaining that their group -- No Justice, No BART -- is asking the BART Board of Directors to shut down the transit agency police department and fire the two officers involved in the July 3 shooting of Charles B. Hill, a 45-year-old transient who BART officials say was carrying a liquor bottle and a knife on the Civic Center BART platform and threatening officers. He was shot and killed at 9:45 p.m. July 3, about one minute after BART officers arrived on scene.

The protest Monday was loud and rowdy, but BART officials said no one was injured or arrested.

BART officials said disruptive protests on the platforms with fast-moving trains and large crowds are dangerous.

"These fringe groups have apparently shown no regard for the work of their fellow citizens and, of course, the customers on the train, the elderly -- all those folks who need Civic Center station open and rely on the station," said BART spokesman Linton Johnson.

The protest started out relatively calm at the Civic Center station, but grew increasingly rowdy when a man climbed to the top of a train, protesters jammed the train door entries and uniformed police and volunteers in bright yellow vests tried to move the crowd away from the trains.

Josue Gonzalez, coming from San Francisco Art Institute to take BART's Fremont line on his way home to San Jose, said he didn't mind the delay.

Over the course of the evening, access was denied at some stations, while others were closed and then opened as BART tried to get a handle of the situation.

The protest group formed following the shooting of Oscar Grant III, 22, on the Fruitvale station platform on Jan. 1, 2009, by former BART Officer Johannes Mehserle. Mehserle was convicted of involuntary manslaughter and was recently released after serving 11 months of a two-year sentence.

Also Monday, BART officials said the new police auditor, Mark Smith, is monitoring the agency's investigation into the fatal shooting of Hill and will issue an independent opinion whether deadly force was justified.

Wire services and staff writer Denis Cuff contributed to this report.