RICHMOND, Calif. — A disturbing mystery is unfolding in Richmond, California, where residents say birds are being killed at an alarming rate after landing on a stretch of power lines.

“It’s very traumatic,” resident Maximilian Bolling said. “They just quickly explode, and it’s really violent.”

Ring security video from one homeowner captured a loud pop. You then see a bird fall lifeless to the ground and the passersby gasp. Residents say the “pop” sounds like a BB gun or firecracker and has been happening far too often.

Neighbors say the phenomenon started several months ago, and has since resulted in at least 13 bird deaths. One woman — who lives across from the powerlines in question but wasn’t available for an interview — said she has put multiple birds in her trash can in recent weeks.

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“It was just horrifying,” resident Sharon Anderson said. “I didn’t even know what was happening at first.”

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The resident who lives across from the power lines says she also filed a report with the Contra Costa County Sheriff’s Office, who did not immediately respond to a request for comment.

In the meantime, neighbors have posted signs on poles warning of the danger and urging witnesses to document incidents.

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Neighbors originally thought the birds were being electrocuted by the wires. However, Pacific Gas and Electric Company says the California Department of Fish & Wildlife evaluated several of the bird corpses and they show no evidence of electrocution. Officials believe their deaths were caused by trauma, potentially from a pellet or BB gun or a slingshot.

PGE released the following statement:
“We appreciate the concern of our customers in Richmond about the recent series of bird deaths. We have asked the California Department of Fish & Wildlife to evaluate several of the bird corpses. They have shared that the birds show no evidence of electrocution, and that their deaths were caused by trauma, potentially from a pellet or BB gun or a slingshot. PG&E does not believe that there was an issue with our electrical equipment and agrees that these birds were not electrocuted. Neighbors have asked the Contra County Sheriff’s Office to look into this situation. The pole at issue is compliant with avian safe standards, as established by the Avian Powerline Interaction Committee.”