The first break-in happened sometime between 2-8am yesterday at a home in the Longcroft area of Bonnybridge when two sets of car keys for purple/blue Mini convertible blue 1 Series M Sport BMW were taken.
Registration for Mini is PJ55 ZJE and the BMW, which has a black roof and white wing mirrors, is MF14 BCK.
Officers are eager to speak to two men seen in the area around the time of the break-in.
One is described as white, wearing a tracksuit, dark trainers and a hood. The second was dressed similar and had gloves on.
The second break-in took place at 12.45 today at a home in the Head of Muir area of Denny.
A white Vauxhall Insignia, registration L19 OUS, and a white Transit van were taken.
Officers later recovered the van in the Chryston area of North Lanarkshire. The driver is described as 5ft 6in tall, chubby build, black hair and wearing a dark grey hoodie.
Forth Valley police are appealing for the public to be vigilant following the thefts.
Sergeant Lyne Rushford of the Community Investigation Unit said: “Following the theft on Tuesday morning we received a report that a number of gates in the Longcroft area had been opened. Two men were also seen on private CCTV trying to open a back door to a house.
“We’d urge the public to be vigilant in guarding against opportunist thieves by keeping their doors and windows secured at all times. Keep valuables out of sight by drawing your curtains or blinds on an evening and ensure that car and house keys are kept separate and hidden.
“We’d also ask that anyone who has information about these break-ins, or the whereabouts of the stolen vehicles, get in touch as soon as possible.”
Anyone with information is asked to contact Police Scotland on 101 or contact Crimestoppers anonymously on 0800 555 111.