Less than a month after being vandalized with pro-Azerbaijani graffiti, San Francisco’s Krouzian-Zekarian Vasbouragan Armenian school was again target of a pattern of hate crimes, when the local police reported that shots were fired at the school building over the weekend, Asbarez reports.

San Francisco police officers were patrolling the KZV Armenian School on September 19 when someone fired a bullet that damaged the school’s sign. No one was injured by the gunfire.

The officers were assigned to guard the Krouzian-Zekarian Vasbouragan Armenian school after the campus was tagged with anti-Armenian graffiti in July and the building adjacent to the St. Gregory the Illuminator Armenian Church was set ablaze September 17. An arson investigation is underway.

The officers immediately searched for the source of the gunshots, but no suspects were located. During the search, officers located a damaged sign in front of the school, which appeared to be caused by a bullet, but no injuries were reported.

On Monday, a spokesperson for the FBI in San Francisco said the agency was aware of the incidents and in“regular contact with local authorities.”

“Should information come to light of a potential federal violation, the FBI is prepared to investigate,” the agency said.