A man was arrested Monday for throwing firecrackers outside the north lawn of the White House.

Alexander Sahagian, 52, threw the firecrackers over the White House north fence, causing noise that sounded like gunshots. Sahagian chose a particularly bad day to fool around, as security was high following the shooting rampage at the Washington Navy Yard, where at least 12 people died, earlier that day. According to the Washington Post, the firecrackers were set off just 12 hours later.

Secret Service immediately took the man down after setting off the fireworks. No shots were fired, but USA Today reports that the White House participated in a lockdown as soon as the firecrackers were heard.

Politco further reports that following the incident, two blocks of 17th Street NW and a block of Pennsylvania Avenue was shut down to everyone but Pedestrians.

Sahagian is being held at a nearby police station and although he has not yet been charged, he likely faces charges for illegally throwing a projectile.