QUINCY, Mass. -- Quincy Mayor William Phelan said a tentative contract agreement has been reached to end a four-day strike by public school teachers in his city.

"Tomorrow the school bells will ring again the city of Quincy," Phelan said at a noon time news conference Wednesday.

More than 900 of the city's teachers have been out on strike since last Friday, in defiance of a court order requiring them to return to the classroom. As they returned to the picket lines Wednesday morning, a $150,000 fine was imposed as a penalty.

Phelan would not give details of the contract agreement, saying that the teachers' union had to review the proposal. He said they scheduled a meeting for 1 p.m. That is one hour before a scheduled Norfolk Superior Court hearing at which a judge could have imposed additional fines on the union.

"I am certain that both parties, and an overwhelming majority of teachers want to get back to the classroom," Phelan said, congratulating everyone involved in grueling negotiations over the past four days for their work.

The strike postponed final exams for many students and left parents scrambling to make child care arrangements.

The key issue in the dispute was health care costs. The teachers opposed a move by the city to require them to pay 20 percent toward their health care premiums, rather than the current 10 percent, saying that the increase would all but wipe out any anticipated salary increases.

The strike raised tensions in the city, where many residents and parents said they have to pay rising health care costs and questioned why the teachers felt they should be exempted from having to pay more.