According to Sussex Police, officers have identified three incidents which are being treated as linked and reportedly took place in supermarket car parks.
Police have released a picture of a man, who they would like to speak to in connection with the incidents.
On Saturday (March 20), at 1.15pm, an elderly woman was unloading her shopping in Tesco, Shripney Road, when a man approached and asked for help with his car.
Police said the woman directed him to the store to ask for help and later noticed her wallet missing from her handbag. She cancelled her cards but £490 had already been spent.
At 3.15pm on Thursday, February 18, a woman was unloading her trolley at Sainsbury’s in Shripney Road when she was approached by a man who said his car was broken.
Police said the victim saw another man take her purse from her handbag. He put it back and they left the scene.
At 3pm on Sunday, February 7, while unloading shopping outside Sainsbury’s in Shripney Road an elderly female was approached by a man who said she had a scratch on her car.
Upon checking her wallet later that day, she discovered that her bank card had been stolen and £1900 has been spent, police said.
"These incidents have had a significant impact on the victims and we are keen to identify the suspect pictured," PCSO Lisa Fowler said.
"If you have seen this man or know who he is, then we would like to know so we can speak to him about these thefts.
"We would also encourage anyone else who may have been victim of this sort of crime to report it to us either online or by calling 101, quoting 1500 of 20/03."