A watch reportedly belonging to footballer Jesse Lingard was stolen from a changing room during a Premier League match.
Met Police officers are investigating a report of the burglary at the London Stadium, home of West Ham United, on 9 May.
On that day, the Hammers lost 1-0 to Everton with England international Lingard playing the full 90 minutes.
A Met spokesman said no arrests have been made and inquiries were ongoing.
Lingard, who was on loan from Manchester United at the time, has a collection of high-end watches, some thought to be worth six figures, according to The Sun who first reported the burglary.