An Alabama teen was seriously injured when her stepfather mistook her for an intruder in their home and shot her, authorities said.

The incident occurred around 2:15 a.m. Sunday when the 15-year-old girl was dropped off from a friend’s to her home in Clayton, news station WIAT reported.

“Her parents heard the garage door open and thought someone was breaking into the home,” Jefferson County Sheriff Sgt. Joni Money told the Trussville Tribune, adding the family was not expecting the teen to return that night.

The stepfather grabbed his firearm and went to investigate the noise, authorities said. When he encountered the teen, he opened fire and stuck her in the abdomen.

She was rushed to a nearby hospital, where she is being treated for serious injuries, the outlets reported.

Authorities haven’t released the identifies of the stepfather or the teen.

It’s unclear whether any charges have been filed in the case, but authorities are continuing to investigate the incident.