SAN FRANCISCO (CBS SF) — A car that was spotted last month during what San Francisco police called “an illegal exhibition of speed event” that included a person waving what looked like an AK-47 rifle out of a window was seized Wednesday, authorities said.

The information came from a Twitter post by the San Francisco Traffic Safety account. The post said that the passenger was seen leaning out of the window of a Cadillac with the weapon in the area of Barneveld and McKinnon on July 11.

Police said that officers with the department’s traffic division were able to investigate the case and identify the vehicle.

While the post did not state whether anyone had been arrested, it did say the vehicle in question was seized and impounded on Wednesday.