On March 1, at around 3.50pm, the victim – a woman in her 80s – was in the carpark of the Waitrose store in Churchill Way when she was approached by two women who had arrived in the car park in a black car with a man.
The women said they were collecting money for charity, and the victim gave the women a small amount of cash.
One of the suspects gave the victim a hug, at which point her necklace was stolen – although the victim didn’t realise until later.
The suspects then walked towards the exit, and it is believed they were then picked up outside by the man in the black vehicle.
Officers are appealing for anyone who saw this incident to please get in contact with Police on 101 quoting reference 54230022601.