US police shot and killed a 15-year-old student after he summoned officers to a high school carpark in San Diego and pointed a BB gun at them, authorities said.

The bizarre incident began when Torrey Pines High School student called the police emergency line and asked officers to check on the welfare of an unarmed boy in front of the school, according to a police statement.

He didn’t name the boy, but investigators later determined he was referring to himself.

When two officers arrived, they spotted a youth in the front parking lot. As they got out of their patrol cars, he pulled a gun from his waistband and pointed it at an officer, police said.

The officers drew their guns and ordered him to drop the weapon. But instead he began to walk towards one of the officers, ignoring more demands to drop the weapon.

Both officers fired, hitting him several times. They performed first aid and summoned paramedics, but the teen was pronounced dead at a hospital, police said.

The gun was found to be a BB air pistol.

Police didn’t release the teen’s name because of his age.

“Our hearts go out to the student, his family and his friends,” said a statement from Eric Dill, superintendent of the San Diego Union High School District.
-with AAP and ABC