Police are warning west suburban residents to lock their cars after two vehicles left running were stolen in Geneva this week.

The unlocked cars were reported stolen about 2:30 a.m. Sunday in the 900 block of Lewis Road, and about 3 a.m. Tuesday in the 200 block of West State Street, according to Geneva police.

A third unlocked vehicle, which was not running but had the keys inside, was stolen about 7 a.m. Dec. 8 in the 1800 block of Belter Court, police said.

“The convenience of a warm car is welcomed during the winter, but it is also an invitation for thieves to steal a vehicle, which can be done in just a matter of seconds,” a statement from police said.

Police advise residents not to leave their vehicles running unattended, whether or not the doors are locked.