A little more than a month after police in Oxnard, CA found a chemical weapon inside a Walmart store, officials say they’ve arrested a 31-year-old man accused of putting it there.

Officers responding to the scene on June 18 identified the device as a “possible improvised chemical weapon,” KTLA reports, and evacuated the building. A hazardous material team successfully disabled the device after six hours.

That time accounts for about $120,000 in losses, Walmart said.

Surveillance footage of the area showed a man leaving the store around the same time as the device was found, police said. After investigating the incident for a month, police identified a suspect who was already in jail on another, unrelated charge.

Officials say he confessed to the crime, saying he was aware that the device would create a gas that could be dangerous, and that he’d looked up how to make it on the internet.

He’s been booked in jail on suspicion of unlawful possession and manufacturing of a chemical weapon of mass destruction.

This isn’t the first time we’ve heard of bad consumers leaving dangerous chemicals at Walmart: last year, police in Indiana found an active meth lab in the bathroom of a Walmart store.

Man Arrested After Allegedly Planting Chemical Weapon at Oxnard Walmart [KTLA]

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