Three people were shot dead in a house Saturday in what police said was an apparent murder-suicide. A 6-year-old boy was in critical condition.

The man believed to be the shooter was among the dead, police Sgt. Cindy Walker said. The boy's mother and another man also were killed.

The boy, who was shot in the head, was taken to a Wichita Falls (search) hospital and pronounced dead. However, brain activity was detected and he was airlifted to a hospital in Dallas, Walker said. Officials said the boy was in critical but stable condition.

Walker said the key witness was a mentally challenged woman who lives in the home where the people were killed, and had not been able to provide much information. The woman's mother told the Wichita Falls Times Record News (search) that the shooting was probably related to a lover's quarrel.