Wildlife experts, police investigators and a power company in Richmond, California, are investigating a disturbing trend of birds mysteriously “exploding” and dropping dead.

It was initially thought the birds were being electrocuted while perched on a set of power lines above a residential street in the Bay Area neighborhood. However, an electric company in that area issued a statement saying they looked into it and there were no issues with their equipment, ABC News reported.

Pacific Gas & Electric then sent two dead birds to the California Department of Fish and Wildlife for examination, which determined the injuries were consistent with trauma that could possibly have been caused by pellet gun, BB gun or a slingshot, according to ABC7.

Law enforcement in the town has responded to the street to investigate, while neighbors have posted signs on poles warning of the danger and urging witnesses to document incidents.

Richmond resident Maximillian Bolling told KGO-TV in San Francisco that he witnessed several birds suffer an awful death after perching on power lines.

“So when they land and it happens, they just quickly explode and it’s really violent,” Bolling said.