Picture: @mertennikell/Twitter

Los Angeles - At least two adults were killed and two other persons, possibly students, were struck by gunfire in a classroom shooting on Monday at a Southern California elementary school, police and fire officials said.

San Bernardino Police Chief Jarrod Burguan said the shooting at Northpark Elementary School in San Bernardino, about 65 miles east of Los Angeles, appeared to a "murder-suicide," but details were sketchy.

"Two adults are deceased in a classroom," the chief said in a Twitter post, adding, "There are two wounded, possible students," who were taken to hospitals. He said their conditions were not immediately known.

"We believe the suspect is down, and there's no further threat," Burguan said.

Authorities did not immediately furnish additional details about the circumstances surrounding the shooting, or the identity and motive of the shooter.

ABC News, citing information from a police spokeswoman, earlier reported that three people, including a teacher, were hit by gunfire, in addition to the shooter.

The San Bernardino County Fire Department said in a Twitter post that there were "multiple gunshot victims" from the incident.

The elementary school was evacuated, and students were bused to a nearby high school where parents, grandparents and other relatives were waiting.

Aerial television footage from the scene showed children holding hands and walking single-file across the campus from the school building to waiting school buses.

One young student, reunited with her mother, told local NBC News affiliate KNBC-TV that Monday's ordeal left her "super scared." Anxious parents interviewed on camera said they had been given no information from the school other than where their children were being taken.

The city of San Bernardino was the scene of a shooting rampage on Dec. 2, 2015, when a husband and wife killed 14 people and wounded more than 20 others at a holiday office party.

The couple, Syed Rizwan Farook, and his wife, Tashfeen Malik, who authorities said were inspired by Islamic extremism, were killed by police during a shootout. 

Reuters