Firefighters were called to a gas leak at a range of shops on Regent Street.
A gas main ruptured below ground level and gas leaked into the basement of an adjacent premises.
Around 150 people were evacuated from buildings in the area by the Metropolitan Police Service and a 50m cordon was put in place as a precaution.
The Brigade was called at 1352 and the incident was over for firefighters by 1722. Two fire engines and two fire rescue units were on the scene as well as additional support vehicles.