A mum has been left heartbroken after an opportunistic thief stole her £1,100 watch seconds after she dropped it in a changing room.

Debbie Jackson, 43, had been swimming at Witham Leisure Centre in Spinks Lane when her jewel-encrusted Raymond Weil watch slipped from her wrist and fell under the cubicle wall.

In the 30 seconds it took Mrs Jackson to realise it had fallen off, the person in the next cubicle had snatched it and left.

The square-faced gold and silver watch, which has diamonds set around the face and a sapphire on the winding stem, was the mum-of-two’s 30th birthday present which her family all chipped in to buy.

She said: “I was calling out and crying but the person in that cubicle was gone by the time I was dressed.

“It’s got so many memories to it - it’s like losing an engagement ring."

Mrs Jackson got out of the pool on March 19 at 9.30am, showered for five minutes and then changed in the cubicle, which has a six-inch gap below the dividing wall.

She dropped the watch within a ten minute window between 9.40am and 9.50am.

The timepiece has pearlised dial with diamonds in place of numbers, except for 12, three, six and nine and would cost around £2,000 to replace.

A force spokesman said: “We received reports that a ladies’ watch worth a four-figure sum was stolen from Witham Leisure Centre in Spinks Lane.

“Anyone with information call Braintree Police on 101.”