The San Bernardino police chief says two adults are dead after a shooting at an elementary school.

San Bernardino Police Chief Jarrod Burguan says on Twitter that investigators believe “the suspect is down.” He says there is no further threat to the school. Burguan says the shooting is believed to be a murder-suicide stemming from a domestic dispute.

A spokeswoman for San Bernardino City Unified school district says one of four people shot in a classroom was a teacher.

Police Capt. Ron Maass says, “The children we do not believe were targeted. The suspect had come to the classroom to visit. The adult female was in the classroom.” The two wounded students are in critical condition.

Police did not identify the shooter or the teacher.