SAN ANTONIO — UPDATE: The boyfriend of the woman found dead in a far northwest side home has been charged with capital murder.

According to police, 50-year-old Casey Farell Marshall called 911 to report he killed two people.  When they arrived they found an 11-year-old girl and a 48-year-old woman dead on the bathroom floor.

It was originally reported by police the child was 12 years old. 

Marshall was transported to police station headquarters for interrogation and subsequently booked for capital murder.

ORIGINAL STORY: San Antonio police are investigating the deaths of a woman and a child on the Far Northwest side of the city.

According to police,  at 5:30 a.m. Saturday they responded to a call on Beaudine Avenue about an assault in progress. When they arrived they found a 12-year-old girl and a woman in either her late 30s or early 40s dead on the bathroom floor.

Investigators believe they were struck by a hand tool. A 50-year-old man, is being detained for questioning. He is the same man who called first responders.

This is a developing story. We will provide updates as more information become available.