ST. LOUIS - Police say there was an extreme rise in car thefts from Friday through Sunday, with incidents reported at several gas stations and car washes citywide.

On Monday, St. Louis Metropolitan Police held an urgent news conference, warning the public about an alarming crime trend. At least a dozen incidents were reported over the weekend.

"Over the weekend, there were multiple vehicle thefts and thefts from vehicles where individuals were pumping gas at area stations. These crimes are not new, but there were multiple instances of thefts that were happening since Friday," Lt. Col. Renee Kriesmann with SLMPD said.

According to police, 39 percent of stolen vehicles this year had keys in them, and nine percent were left running. Most of these crimes involved thieves targeting unlocked vehicles with valuables like purses or wallets left in plain sight.

Many of the thefts happened during broad daylight between 8 a.m. and 6 p.m.

"The thieves then drive up to the victim's car, open the unlock door, and grab valuables that are within reach. The thief then quickly drives off. It happens in a matter of seconds," Kriesmann said.

Workers at a gas station on Hampton Avenue told FOX 2 off camera that car thefts happen so often that police installed a real-time crime camera to monitor activity.

Police confirmed at least one theft this weekend involved a stolen firearm at another establishment in the city. Police are asking the public to lock your doors, turn off your car, and secure your valuables.

Law enforcement has increased patrols across the city and is investigating if these incidents are connected. They're also recommending gas station owners increase security to help prevent these crimes.