"London Fire Brigade and London Ambulance Service were called to the scene.
"Ten people have been treated for minor burns at the scene and taken to east London hospitals by LAS.
"Another two people presented themselves at an east London hospital with similar injuries. All victims' injuries are non-life threatening."
No arrests have been made and police are investigating the incident.
Stuart Crichton, LAS assistant director of operations, said: "We were called at 1:09am today, Monday 17 April, to reports of an incident on Warburton Road, E8.
"We sent multiple resources to the scene including paramedics in cars, ambulance crews, a number of officers an advanced paramedic and our hazardous area response team.
"We have taken 10 patients to hospital."
Around 200 people had left the premises before the arrival of emergency services, with a further 400 evacuated from the building.