Two homes were burgled in Moville and six cars broken into in Buncrana on Tuesday night.
The burglaries took place at Mill Glen, Glencrow as residents were watching TV.
The cars were broken into at the Summerhill and Burwood estates in Buncrana.
There is no suggestion the incidents were linked.
Two victims, Paul McGowan from Mill Glen and Mark Gribbons from Summerhill, Buncrana said residents of the estates have been left “extremely unsettled” by what occurred.
Mr McGowan told how he was “shocked at how easily it happened.”
He said: “There is a good chance it took place while we were in our living room watching TV. I lost a large sum of money and two expensive watches.”
Two laptops belonging to Mr McGowan and his housemate were left “untouched”.
He said: “It’s left our housing estate really unsettled as there are so many children living here, always out playing.” A home next to Mr McGowan’s was also targeted.
Another resident said they were “angry” they Gardai hadn’t informed or warned them about the burglaries.
In Buncrana, Mr Gribbons said he first learned of the car thefts at the Summerhill and Burwood estates when Gardai called to his door.
He said: “They asked me to check my car and sure enough, it had been broke into. A key of a mobile home we own had been taken from the car. We found it at the door of our house, which was very unsettling. They must have thought it was the house door key.”
A number of purses, a handbag, a satellite navigation system, a mobile phone and cash were taken from the cars. It is understood none of them were locked.
Buncrana Garda Superintendent Mr Eugene McGovern confirmed Gardai were investigating the incident. He also appealed to motorists to ensure their vehicles are locked at all times and not to leave valuables within them.
Buncrana Councillor Ciaran MacLochlainn said the latest incidents show that Garda numbers need to be increased in the peninsula.
“Garda numbers are down 28% in inishowen since 2007,” he said.
“That’s twice the Donegal average and almost three times that across the State. That’s a real issue for our communities. When the Gardai have the numbers and intelligence they can defeat these criminals that plague our communities.”