When normally safety-conscious firemen park their cars too close to railroad tracks, Prince George's volunteer fire chief Donald Strine said yesterday, "accidents will happen."

So it was Thursday night that as Gov. Harry Hughes and County Executive Lawrence J. Hogan were lauding the efforts of the county's 1,100 volunteer firefighters at their annual dinner in an Upper Marlboro warehouse, a freight train rammed three cars that belonged to guests at the dinner and pushed them into six others parked nearby.

No one was injured in the accident, which occured at 8:40 p.m. near Rtes. 725 and 202, according to police. The collision took place during a heavy downpour that may have encouraged several dozen of the 600 firemen, decked out in dress uniforms for the occasion, to park along the nearby tracks instead of the limited parking facilites farther from the entrance, according to Strine.

"Some cars were parked too close, and the freight train just took care of them," said Strine, a full-time District of Columbia firefighter and Prince George's volunteer for 26 of his 40 years.

"You can safely assume that if a car was struck by a train, the car was on the right of way," Conrail spokesman Steve Lubetkin said yesterday. "Trains can't stop on a dime."