Petrol that had spilled into an open sewer caught fire and sent a wave of flame through a densely populated slum in the Kenyan capital, Nairobi, killing more than 100 people.
Police said 75 bodies had been recovered following the fire on Monday but it was proving difficult to establish the exact number of dead.
Residents said petrol spilled from a fuel depot owned by the Kenya Pipeline Company (KPC) and ran into a sewage dyke that runs under the slum, known as Sinai. The petrol ignited, causing an inferno.
Police spokesman Charles Owino said the fire was started by a cigarette butt tossed onto the dyke, which opens into a small river.
Authorities said they were battling the fire in an area estimated to be just over an acre.
Police said some of the slum's residents were killed while trying to scoop up the fuel from the burst pipe and from the sewer. Many had hoped to sell the petrol on the black market.
Energy Minister Kiraitu Mutungi said the government had unsuccessfully tried to move people squatting in the area reserved for the pipeline.
Residents have in the past refused to move despite repeated warnings, saying they had nowhere else to go to.
Local media berated the government and KPC for poor safety standards and inadequate disaster preparedness.