FERGUSON, MISSOURI: Activists on Saturday called for mass civil disobedience on the highways in and around this St. Louis suburb to protest the killing of an unarmed black teenager by a white police officer, with the leaders of one coalition encouraging supporters to stop their cars to tie up traffic on Labor Day.

The announcement came at a peaceful, if at times tense, march and rally on Saturday that drew more than 1,000 demonstrators to some of the same Ferguson streets where the police clashed with protesters in the days after the killing of Michael Brown. Brown, 18, was shot August 9 by Officer Darren Wilson of the Ferguson Police Department, and his bloody body lay on Canfield Drive for about 4 1/2 hours before it was removed.

Organisers at the rally on Saturday called on demonstrators to drive on Interstate 70 and other area highways at 4.30pm on Monday, turn their hazard lights on and stop their vehicles for 4 1/2 minutes to symbolise those 4 1/2 hours that Brown’s body lay in the middle of the street.

“We’re going to tie it down, going to lock it down,” Anthony Shahid, one of the lead organisers of the rally, told supporters from the stage at a Ferguson park. “I want the highways shut down. I know it’s a holiday, but it won’t be no good holiday.”

Shahid’s announcement was met with applause by many of the marchers, but it was unclear how many people would take part. Only a few hundred demonstrators were in the park when Shahid made the appeal, and another organiser suggested that the plan for Monday could change because the action was still under discussion. It was also unclear what the authorities intended to do in response to the civil disobedience plan.

“There will be an appropriate, measured response based on conditions, but we cannot discuss the specifics of operational plans,” said Mike O’Connell, a spokesman for the Missouri Department of Public Safety.

The march and rally were organised by a coalition of black activists and leaders largely from the St. Louis region, including state legislators, lawyers, and representatives of the Nation of Islam, the NAACP, the New Black Panther Party and the Green Party. Organisers with the group, called the Justice for Michael Brown Leadership Coalition, said they wanted Saturday’s event to be a peaceful gathering and had coordinated some of the logistics with city, county and police officials. For much of the march and rally, the police had a very light presence compared with the show of force they had made at other protests.

“They’ve already seen the whole world look at the missteps that they made, how they handled the black community like an army going to war in Iraq,” said Akbar Muhammad, an organiser of the demonstration and a top aide to Louis Farrakhan, leader of the Nation of Islam. “If they had any sense, they will handle it in a tactful manner.”

The march on Saturday showed how difficult it may be to direct the actions of a young, decentralised and assertive protest movement. A mile into Saturday’s demonstration, the march seemed to split, with some heading to a scheduled rally in a public park and others insisting that the marchers continue to the Ferguson police station. Few seemed to know whether the turn into the park was the plan all along or an unscheduled deviation, and several marchers began a chant of “Ain’t no justice in the park!”

“If they stop here a lot of people will feel misled,” said Trinette Buck, 40. She said that the younger protesters were not waiting on leadership, nor were they concerned about what might happen if things turned ugly at the police station.

“There is no fear anymore,” she said. “It’s either stand up or die.”

A few marchers began heading to the police department without waiting for official word, peeling off in small groups and walking along the shoulder for two miles of road, drawing supportive honks from cars along the way. By the time the main body of the march, as well as the demonstration’s leaders, arrived at the police station, well more than a 100 had already gathered and were chanting in a somewhat tense face-to-face confrontation with a line of police officers.

Shortly after 5pm, one of the marchers who had been taunting the police line was surrounded by law enforcement officers and was apparently placed under arrest. It was unclear why.