Authorities are investigating after threatening messages were found scrawled in a Mayfair High School bathroom Tuesday afternoon.

The messages said in part, “Ima bring a gun” and “Friday be prepared,” according to the Los Angeles County Sheriff’s Department and pictures of the graffiti posted on social media.

“It’s actively being investigated, but there’s nothing that’s specific and credible,” Lakewood Station Sheriff’s Lt. Joe Badali said.

The Lakewood campus notified sheriff’s officials about the messages around the end of the school day Tuesday, according to Badali. He said investigators are trying to narrow down who could have written the messages but they haven’t been able to so far.

He said the writing was found in a girls restroom at the campus.

The district notified parents about the situation and is working with law enforcement to make sure everyone is kept safe, according to the superintendents office at the Bellflower Unified School District.

Badali said authorities will sometimes see vague threats like this during busy or stressful times on campus.

“I don’t know if Friday is finals or exams or something,” he said.