SEOUL, South Korea (AP) _ Riot police firing tear gas fought about 2,000 workers trying to march out of the nation's second-largest auto factory today, demanding the release of arrested union leaders, police said.

Police said clash erupted outside Daewoo Motor Co. in the western port city of Inchon when the slogan-chanting workers, armed with clubs and rocks, began marching.

About 800 riot police stopped the march with barrages of tear gas, police said. There were no immediate reports of injuries or arrests.

Daewoo officials said the protest halted operations at the factory, a joint venture between the Daewoo Group and General Motors of the United States.

Shouting ''Down with the regime of (President) Roh Tae-woo,'' the workers accused Roh of suppressing union activities, witnesses said. They said the workers demanded the release of seven union leaders arrested last week on charges of illegally interfering in a shipyard strike.

The seven were caught holding a meeting with 60 other union leaders from 16 major firms to organize sympathy protests supporting the strike at Daewoo Shipbuilding and Heavy Industries Ltd.

The six-day shipyard strike on the southern island of Koje ended last Thursday after 10,000 workers accepted a new contract promising better pay and more union power.