STERLING HEIGHTS, Mich. (AP) _ Striking workers clashed with police Monday night for the second time during the Labor Day weekend, again delaying the city's newspapers from leaving the printing plant.

Police wearing riot gear tried to open a path for replacement workers to make their way into the Detroit Newspapers printing plant but were pushed back by more than 100 stick-throwing protesters.

Police responded by spraying pepper gas. The protesters, some of them wearing gas masks or surgical masks to cover their noses and mouths, used their picket signs to fan the pepper gas. Two were arrested, according to broadcast reports, and two were treated at an ambulance at the scene.

``I was just standing there, just holding my ground, like everybody else, and they sprayed their pepper spray and it got in my eyes and my mouth and I couldn't breathe,'' said John Prainito, 31, a striking mailer. ``I thought I was having a heart attack.''

He said he was given oxygen and police took his name. Others who remained on the picket line used ice and water to try to clean the pepper gas from their eyes.

A long line of vehicles carrying the replacement workers remained lined up along the median waiting to get inside briefly, but by 11:15 p.m. all the vehicles had left.

No Tuesday newspapers had been moved from the plant, Detroit Newspapers Vice President Susie Ellwood said. The first load of papers usually rolls out between 9 p.m. and 10 p.m., she said.

Although far fewer protesters were involved, the scene was reminiscent of Saturday when more than 3,000 union members rallied outside the plant and delayed delivery of Sunday editions of The Detroit News and Free Press by nearly 12 hours.

Earlier Monday, striking newspaper workers touted their efforts Saturday in a massive rally with thousands of other union members.

James P. Hoffa, who had announced his candidacy for Teamsters president, urged members of the six striking unions to remain strong.

``This is true labor here,'' Hoffa said of the rally, which followed the city's Labor Day parade. ``This is where the fight's at _ the newspapers.''

Joe Swickard, a striking Free Press reporter and spokesman for The Newspaper Guild of Detroit Local 22, said he was encouraged by the union showing during the Labor Day weekend.

``We are going to get a fair and reasonable contract,'' Swickard said. ``We are not going to be deterred.''

Detroit Newspapers handles business and printing operations under a joint operating agreement for Knight-Ridder Inc.'s Free Press and The Detroit News, owned by the Gannett Co. Inc. Before the strike, the two papers published separately during the week and a combined edition on weekends; since the walkout, a combined edition has been published all week.

The Free Press and its newsroom workers were scheduled to meet again Tuesday. No talks were set for the News.

Last week, the Free Press made a proposal that the Newspaper Guild did not take to it members; the union offered a counterproposal that management rejected.

``We had very tough bargaining Wednesday and Thursday. I would foresee that continuing. That's the only way we're going to get a settlement is that hard work,'' Swickard said.

The strike began July 13 when six unions representing about 2,500 workers walked off their jobs, mostly over wages and work rules. Their contracts had expired April 30 and been extended day by day until July 2.