Scotland Yard said one man suffered serious burns in the blast, while a police officer has sustained injuries to the arm.
Police had been called to a disturbance at a house on Stapleton Hall Road prior to the explosion, and it is believed bailiffs were at the building.
“Officers attended the location and, as they arrived at around midday, there was a localised explosion within the property,” a spokesperson said.
Following the explosion, the basement of the terraced house was ablaze – as well as part of the ground floor and a shed in the back garden.
Ten fire engines and 72 firefighters were sent to the scene, and the London Fire Brigade said one person had left the property before the emergency services arrived.
The London Ambulance Service said several of its crews, along with an air ambulance and a hazardous area response team, have arrived at the house.
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