On Friday, a North Street resident reported a 2017 silver Range Rover and a 2017 black Mercedes-Benz were taken from the home, said Lt. John Slusarz.
Both vehicles were unlocked and had the keys inside, he added.
"Car thefts are continuing in the area and residents should make sure to remove the keys," he added.
From Jan. 1, 2017 to Jan. 1, 2018, 79 vehicles were stolen in Greenwich, he said. That double the number from the same time frame the year before.
According to Slusarz, there is a group of thieves that move between the Greenwich, New Canaan, Bridgefield and Westchester County, areas checking for vehicles that are unlocked and may have keys inside.
"The days of breaking the windows of cars and hot-wiring them area over," he said. "It's easy with residents leaving the keys and valuables inside."
Police are investigating the thefts.
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