On Wednesday, Albuquerque investigators announced that they had determined what sparked a fire last month at New Mexico’s National Hispanic Cultural Center: an overnight security guard and his friend accidentally started the blaze by smoking a fake joint.

The guard, Matthew Luxon, and his friend, Lyle Thompson, used bar receipts as rolling papers. Instead of cannabis, they used “actual weeds,” wrote KOB4 News.

Investigators said the fire started while the two men took selfies with the faux doob. After lighting it up, one of the men dropped the burning joint during a coughing fit. The fire tripped an alarm, alerting Luxon’s security company.

Allegedly, Luxon lied to his employers and told them nothing was wrong. Then he and Thompson left the scene while the emergency sprinklers ran for four hours.

Albuquerque police charged both men with negligent arson and conspiracy. Luxon caught an additional charge for tampering with evidence.

Initially, the estimated cost for repairing the damages sat at half a million dollars. But an updated estimate places that cost closer to $1.5 million.

That’s one expensive selfie. Pricier than a Banksy, even.

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