A woman swindled a good Samaritan out of £50 by claiming she could not pick up her baby, because she had no money to pay for the fuel needed to get there, Sutton police said.

According to officers, the woman, "in between sobs" told the 20-year-old man she did not have her purse, that her mobile phone had died and she needed to get from the Cheam store to Hammersmith to collect her baby from a friend.

A spokesman said: "The man, who had come out of the Tesco store in Oldfields Road where he worked, offered the woman his mobile phone so she could call a friend or relative for help but she said she didn’t know any of their numbers by heart."

He then "generously offered her £30 to pay for her journey" but as they walked together to the cashpoint nearby, she "persuaded him to withdraw £50 ‘just to be on the safe side’."

Sutton police said the white, blonde, 35-year-old 5ft 6in woman, who spoke with a London accent, promised to return to the store to repay him.

The spokesman added: "He did not see the suspect go to a vehicle or drive away.

"As he started to walk home, he began to realise he had been deceived and reported the incident in person at the front counter at Sutton police station."

Those who witnessed the incident at the ground-level open-air car park outside the store on Tuesday, May 12 between 9.20 and 10pm should contact Sutton Police station on 101.

Alternatively, contact Crimestoppers anonymously on 0800 555 111.