A teenager was seriously injured Friday night when she was struck by a county police car that reportedly was on its way to help quell a fight after a high school football game in upper Montgomery County.

The incident occurred about 9:15 p. m. on Apple Ridge Road in the Gaithersburg area after a football game at Watkins Mill High School, which is in the 10300 block of Apple Ridge.

Mark Sroka, chief of the Gaithersburg police department, said one of the first calls from the scene reported “a fight involving several females.” County police issued a Twitter report saying that officers “responded to large fight” at the school.

A county police cruiser was involved in a “pedestrian collision,” a second police Twitter report said.

An e-mail from Watkins Mill’s principal, Scott Murphy, to the school community said a female 10th grader was struck as spectators were on their way home after the game. The message made no reference to a fight.