When the SWAT team entered the home they found the bodies of Singh, a woman believed to be his wife and two children, Curtice said. All appeared to have died from gunshot wounds.
The 17-year-old suffered severe head trauma and underwent surgery at a hospital where he remained in intensive care Saturday evening, Curtice said.
Singh, 47, was arrested by Selma police in February 2011 when his wife reported that he had choked her, Selma Police Chief Myron Dyck said shortly after that arrest. Police then discovered that he was being sought in India, but Dyck said at the time that he could not keep Singh in custody on the murder charge without a warrant from international authorities.
Several days later, India requested that the United States arrest and extradite Singh. It wasn't clear on Saturday why Singh had remained free since the request. A request for comment from the Consulate General of India in San Francisco on Saturday was not immediately returned.
Dyck didn't immediately return a call seeking comment Saturday about the 2011 arrest, and Selma police referred questions about the apparent murder-suicide to Fresno County sheriff's officials.
Selma police last had contact with Singh about two months ago when he called to complain that reporters wouldn't leave him alone because of the murder warrant, Fresno County Sheriff Margaret Mims told the Fresno Bee.