A watch belonging to Hammers loan star Jesse Lingard was stolen from West Ham's changing room during a match earlier this month.
The watch, reportedly worth a six figure sum, was taken from the Hammers dressing room during the Premier League clash against Everton on May 9.
Lingard's teammates helped the Manchester United man search the changing room for the missing item but after being unable to locate it the police were called in to investigate.
According to reports in The Sun Lingard is devastated to have one of his precious watch collection stolen from him, with a source telling the newspaper.
"Jesse was devastated, but nobody can believe it. It’s completely unheard of for something to be stolen from inside the players’ dressing rooms during a game.
"Security at the stadium is top class. There are staff guarding the tunnel and all those areas — as well as CCTV all over the place.
"Of course everyone has searched high and low but it appears it has definitely been taken, and there was no option but to call in the police. Everyone is gutted for him, he loved that watch and thought it would be safe."
A spokesperson for the Metropolitan Police said: "Police are investigating a burglary at the London Stadium. It was reported that a watch was stolen from a changing room on the afternoon or evening of Sunday, 9 May.
"There has been no arrest and enquiries continue."
Access to the London Stadium is restricted and security, particularly on matchdays, is tight with CCTV monitoring the ground and security patrolling the area.
A West Ham spokesperson said: "The incident happened a month ago and the club took all appropriate steps at the time.
"While we will continue to assist with the matter, we are unable to comment further as this is now part of an ongoing police investigation."
