WASHINGTON — An Adelphi, Maryland, man has been arrested after police say he threatened to bring guns and explosives to his old high school.

Alejandro Avelar, 20, threatened via Twitter to bring the weapons to High Point High School, in Beltsville, on Tuesday afternoon, the Prince George’s County police said in a statement.

He has been charged with threat of mass violence and other related charges, the police said. They add that Avelar, who they say is an alumnus of High Point, didn’t actually have access to guns or explosives.

Police say that if you find a threat of violence on social media, you should call the police immediately — it lets the police trace the origin of the post faster.

If you have any more information about this case, the police ask you to call Crime Solvers at 866-411-8477, text “PGPD” plus your messages to 274637 (CRIMES) or submit a tip online at pgcrimesolvers.com.