A suspect refused to cooperate and barricaded himself in a house.
LAPD Mission Division officers and a SWAT team were called to the scene.
Sylmar Elementary School, across the street from the barricade, was evacuated through the rear of the school as a precaution.
SWAT fired tear gas into the home.
Officers entered the house after 4 p.m. In the process of clearing the house, they discovered the suspect was gone.
The home is located on the 13000 block of Phillippi Avenue.