Gardai say thugs smashed their way into a car at Clar Chapel on Sunday and made off with a sum of money and other personal items.
A spokesman said: “We would once again alert people to the fact this is happening and would ask people never to leave any valuables in their vehicles.”
The victim of the incident was said to be very upset afterwards.
It is the latest warning from Gardai after a series of similar incidents across the county this year, with thieves casing cars at graveyards.
Last week donegaldaily.com also revealed a huge surge in burglaries and thieves target Christmas.
Today a leading computer expert also warned that thieves are getting more sophisticated and are now checking Facebook and Twitter for people who may tell friends online when they are out for the evening.
Niall Mulrine from PC Clean told us: “I would urge people never to put that sort of information online as it is now clear that some thieves are checking social networks and using information gathered to target people’s homes.”