Police were called to the shooting around 1 a.m. at a home in the 4600 block of Croker Ridge Road.
According to officials, a Christmas party was being held at the house where teenagers had gathered when someone inside a small, red vehicle fired about eight shots.
The teen girl was shot in the leg. An 18-year-old man was shot in the stomach and arm. Both are expected to survive.
Police do not believe the victims were targeted.
Officials are still investigating, but say no weapons were recovered at the scene.
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