Beauty spot thieves have been targeting vehicles in the car park at Tidemills, between Seaford and Newhaven.
As a result Sussex Police are warning motorists to be on their guard and to take valuables with them.
Stealing valuables left in cars parked at beauty spots like Tide Mills is common during spring and summer.
The most recent theft was on Saturday April 26 where a wallet, clothing and a Samsung mobile phone were stolen from a blue Suzuki Wagon broken into between 1.45pm and 4pm.
The same day between 2.30pm and 4.45pm a beige Volkswagen Transporter van was forcibly entered by thieves who took a Panasonic stereo, a wallet, a Sony mobile phone and £120 cash.
Sergeant Stuart Mullins, of Seaford Neighbourhood Policing Team, said: “This type of theft at beauty spot car parks is common at this time of year and into the summer.
“Our advice is never to leave valuable items or bags in your vehicle, and if this is unavoidable, to ensure they are hidden from view.
“If anyone sees anyone acting suspiciously around vehicles, they should contact police immediately on 999. Meanwhile, if anyone has any information about the Tidemills thefts, they should phone Sussex Police on 101 or email email@example.com, quoting serials 1022 of 26/4 (Suzuki) or 1097 of 26/4 (VW).
“Alternatively they can contact the independent charity Crimestoppers free and anonymously on 0800 555 111.”