William Hill in Hoe Street, Walthamstow has been closed by police as they carry out an investigation
Police have blocked off an area of pavement after an incident in a betting shop.
Officers have been at the William Hill shop in Hoe Street, Walthamstow since around 12.35pm.
One witness said officers arrived in two cars around an hour ago.
The pavement has been blocked from the corner of Hoe Street to the other side of the bus stop outside the shop.
Police are yet to reveal what action is being taken.
More to follow.
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