HAVERTOWN, Pa. (CBS) -- Haverford Township Police say it's simple.
A group of teens come into a neighborhood, check on car door handles, and in some instances, have "struck it rich" in taking people's belongings.
For the first time — CBS News Philadelphia has been able to verify reports of hundreds of car thefts from all over the Delaware Valley are the work of a group of teenagers from Wilmington — according to a law enforcement bulletin chief Investigative Reporter Joe Holden has obtained.
In videos obtained exclusively by CBS News Philadelphia Investigations — it appears a group of teens goes from car to car in an area off Brookline Boulevard in Havertown.
One person carried a flashlight and ran back to a car police say was stolen.
Police say a total of 31 unlocked cars were entered and personal belongings stolen on Monday night in the Oakmont, Brookline and Chatham Park neighborhoods of Haverford Township.
On Tuesday, police say they received three dozen complaints of theft from unlocked cars. In addition, two cars were stolen.
"You can see a black Honda going down the street, probably four or five look like teenagers inside, three of four walking alongside going to the street trying car doors," Haverford Township Police Chief John Viola said. "As they go along, if they find anything valuable, they grab it. If they find the keys in the car, the car's gone."
Chief Viola says the group of teens stole two cars Monday night.
"This band seems to be the same one that's working the whole Tri-State area and not just a Pennsylvania or Delaware County, we've had liaisons from New Jersey and Delaware," Chief Viola said. "We feel that they're coming out of Delaware in the same stolen car work and then work in the areas."
In dash camera footage below, officers unsuccessfully attempt to intercept a stolen BMW near Pembroke and Manoa – the teen driver hops the curb and destroys a fence.
After the driver of that stolen BMW SUV took out a fence, they headed south on Route 1, then hopped on the Blue Route.
Police say the car, thanks to GPS technology, was recovered just north of Wilmington, Delaware.
Law enforcement sources shared a bulletin with CBS News Philadelphia — showing photos of the teens allegedly behind the thefts and the stolen cars detectives say they use to travel back and forth from an unknown location near Wilmington.
Sources tell CBS News Philadelphia Investigations the group has been linked to hundreds of theft cases in South Jersey, Delaware and across the Philadelphia suburbs.
Carolyn Brady recently installed a camera system because of the car break-ins.
"It's there for my protection, for their protection and that's the way we're gonna play the game here," Brady, of Havertown, said. "We have to stay one step ahead."
Given the volume of thefts and the crossing of state lines — it wasn't clear if federal law enforcement had become involved.
A spokesperson for the FBI couldn't confirm if there was an investigation.
Police say to not engage with the teens. They urge anyone who comes in contact with them to call police.
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