PORTLAND — Four children had to be transported by ambulance to Maine Medical Center earlier tonight after their school bus collided with a car on Forest Avenue.

Lt. Mike Jones said the bus, which was being used by the Cumberland County YMCA, was returning to the YMCA from its Otter Pond day camp in Standish with about 20 children on board.

Jones said a car swerved in front of the bus near Forest Avenue and Marginal Way as the driver attempted to change lanes, forcing the bus driver to come to an abrupt halt.

The bus suffered minor front end damage. Several children – between the ages of five and eight – sustained bumps and bruises and were taken to the hospital as a precautionary measure, Jones said.

Two camp counselors were also on the bus when the crash occurred shortly after 5 p.m.