The wreckage of a Cirrus SR 22 airplane is shown in this handout photo courtesy of WBAL-TV/SkyTeam11, near Frederick Municipal Airport in Frederick, Maryland October 23, 2014. [Photo/Agencies]

FREDERICK, Maryland - A fire department official says three people were killed and two others were injured when an airplane and a helicopter collided in midair at an airport in Maryland.

Capt. Kevin Fox of Frederick County Fire and Rescue says the collision at Frederick Municipal Airport occurred at 3:40 pm.

He says it's not clear how the collision occurred or which victims were aboard which aircraft.

The injured victims were taken to a trauma center in Hagerstown. Fox did not know the extent of their injuries.

Aerial footage from WJZ-TV in Baltimore showed an airplane that had crashed into a stand of trees.

The airport opened in 1948. It has two runways.