"During an illegal exhibition of speed event at Barneveld & McKinnon, a passenger leaned out of a Cadi holding an AK47; see photo. SFPD Traffic Company personnel worked up a case, and seized this particular vehicle today," the San Francisco Police Department wrote on Twitter, accompanied by photos.
The Cadillac was found by authorities and towed on Wednesday.
"The incident is being investigated by the SFPD Stunt Driving Response Unit and the SFPD Traffic Company," the San Francisco Police Department told Fox News, adding they could not comment further as it is an active investigation.
The incident comes after police reported an uptick in shootings and assaults in the city during the first six months of the year.
The city reported 119 shootings, both fatal and non-fatal, for the first six months of 2021, compared to 58 in the first half of last year.
"We’re almost double where we were in the last two years, and that is a huge concern," Police Chief Bill Scott told reporters during a mid-year report last month.
He added at the time that robberies were down in the city despite viral videos showing people brazenly shoplifting from stores in the city.
In one incident last month, 10 people were seen taking designer handbags from a Nieman Marcus in Union Square, and leaving the scene in vehicles that were waiting for them outside.
The uptick in shootings in San Francisco comes as murders increased by 16% in major cities across the nation, according to the Council on Criminal Justice's (CCJ) pandemic crime report.