Police are warning householders to be on their guard following a spate of distraction burglaries.
Incidents inolving elderly residents have been reported in Brighton and Hove and Crowborough.
In Freshfield Road, Brighton, an elderly couple in their 80s allowed a man into their home, only to find later that he had stolen a wallet before riding off on a bright red bicycle.
The incident occurred at about 6.50pm on May 21 and the suspect is described as being in his mid-20s, 6ft, slim, clean shaven and wearing blue trousers and a sweat shirt. He was carrying a small black bag.
At 6.30pm on the same day, a 77-year-old man who allowed three men into his house in Blackness Road, Crowborough, to clean windows.
He later found four blank cheques had been stolen.
The men were believed to be using a grey Mitsubishi L200 pick-up in which they had a jet wash hose.
On May 22 at 5.30pm a man called at an elderly woman's flat in Westbourne Street, Hove, saying he was from the Community Health Service and needed to check her pulse.
Once inside, he asked for a cup of tea and when she returned from the kitchen it was to find the man bent over near her handbag.
She then discovered her purse was missing.
The suspect was a white man in his 20s, 5ft 10in, thin, with short hair and wearing jeans and a navy blue jacket.
The Brighton and Hove incidents may be linked.
Police are also aware of an incident that happened in Rottingdean on May 20 at 8pm but was only reported on May 22.
A woman wearing a blue uniform knocked on the door of a 78-year-old woman claiming to be a carer.
It is not known if anything was taken but the matter is still under investigation.
All these incidents involved the use of plausible excuses to gain entry to the homes of vulnerable elderly people.
Anyone who may have information about any of these or similar occurrences is asked to phone Sussex Police on 101 or email firstname.lastname@example.org, quoting serial 1290 of 21/5 (Brighton), 1254 of 21/5 (Crowborough), 1221 of 22/5 (Hove) or 1140 of 22/5 (Rottingdean).