The Kenyan authorities have set up two task forces to investigate the cause of a fire which ripped through the city hall of the capital Nairobi.
Firefighters ran out of water as they tackled the blaze
The blaze started at 0200 local time (2300 GMT on Monday), sending sheets of orange flames into the night sky.
Several floors were gutted by the fire but there are no reports of casualties as the building was empty at the time.
It is not clear what started the blaze, which comes as the council is embroiled in several financial disputes.
City officials said it took five hours to bring the fire under control.
Council fire engines were unable to cope on their own and several ran out of water as no working hydrants could be found near the city hall.
It required a combined force of army, air force, airport authority and other private fire brigades to stop the flames.
Following a crisis meeting of key ministers, Vice-President Moody Awori cautioned against speculation that the fire had been started deliberately.
But assistant Tourism Minister Fred Gumo said he thought it was sabotage.
Among the thousands of documents destroyed were maps showing the routes of new road bypasses.
The council has recently started demolishing structures illegally built in their paths.
Phones 'cut off'
Investigators from the government's efficiency monitoring unit were also conducting a probe into the council's finances in a bid to resolve its persistent cash flow problems.
City council workers are on strike because their wages have not been paid for three months.
Some reports said the council's phones had been cut off because of unpaid bills and a guard on duty at the time was forced to walk a mile to the central police station to report the fire.
The council is embroiled in financial disputes
Nairobi Deputy Mayor Lawrence Ngacha told the BBC's Network Africa programme that the fire started in the middle of the third floor and spread quickly after igniting roofing tar.
The whole of the engineering section of the building and part of the health section were destroyed, as well as the council chamber and the main hall used for official functions.
Mayor Joe Aketch was not in Nairobi during the fire but said it had destroyed the records of the city's sewers, town-planning and wires.
"Everything is down. Charter Hall, which really - it's a symbol of this country - is virtually down," he said.
Two Nairobi slum areas have also been ravaged by fires in recent weeks.
Some residents of the South B neighbourhood, which was hit by fire on 20 February, suspect they are being forced out to make way for new roads.
A major fire in another slum area last month left half of Nairobi without power for two days.