The Los Angeles County Sheriff’s Department is investigating a viral video showing Antelope Valley teenagers shouting the n-word and other racial slurs as one teen’s face is painted dark brown, authorities said Thursday.

The clip was posted to Snapchat before being viewed thousands of times elsewhere — a Twitter post made Sunday afternoon shows the video had received 340,000 views by Thursday morning.

It shows a girl painting dark make-up onto another teen’s face as others off-camera giggle and shout the n-word at him.

“We were recently made aware of a social media video showing a group of teenagers exhibiting deeply offensive, and inexcusable racist behavior, ” the Antelope Valley Union High School District said in a written statement. “We are working on identifying those in the video, while including our law enforcement partners, and will take action as deemed appropriate.”

Sheriff’s officials with the department’s Lancaster station are now investigating the incident.

“Lancaster Sheriff’s Station diligently works hand in hand with the staff and administration at all of our Antelope Valley Union High School District schools, and although this incident took place off campus, we take all matters regarding our students very seriously,” Ali Villalobos, spokesperson for the department’s Lancaster station, said in a statement.