A student was arrested for allegedly making threats to harm another student, prompting a brief lockdown at Oxnard High School on Wednesday.

Around 2:30 p.m., a school resource officer at the campus located at 3400 W. Gonzales Road received information that there was a discussion between a female student and a male student in the library that turned into a disagreement, the Oxnard Police Department said.

The male student evidently became upset and left, according to police, who added that the two had dated for a brief time.

The teen later sent the girl a message through social media with a photo of what appeared to be a gun threatening to harm another student, Oxnard Police said.

The school resource officer and the school’s administration thought the photo may have been sent from the campus, and out of an abundance of caution put the high school on lockdown while officers searched the campus.

The student was located off campus on Channel Islands Boulevard near Manzanita Drive and was arrested on suspicion of making criminal threats. He was taken to Juvenile Hall.

The weapon was located and determined to be a BB gun, police said.

Out of caution, the department placed additional police units on and around the Oxnard High School campus Thursday.