NAIROBI - A loud explosion sent thick smoke billowing from the Nairobi mall where militants from Somalia's al-Qaida-linked al Shabaab group threatened to kill hostages on the third day of a raid in which at least 69 have already died.
The blast was followed by other smaller detonations and volleys of gunfire but there was no indication of the fate of people whom the authorities say are being held by 10 to 15 Islamist gunmen who took the complex by storm on Saturday.
As troops ran into new positions, security official told Reuters at the scene: "It is us who caused the explosion, we are trying to get in through the roof."
A plume of oily black smoke was still pouring from the building after 15 minutes.
A senior officer had said police were "closing in" on the militants after rescuing more trapped people overnight. But officials have been suggesting since Sunday that the siege may be near an end, while the guerrillas seemingly remain at large.
Interior Minister Joseph Ole Lenku said "a few" people were still hostage: "Our disciplined forces ... have been extremely careful to find the balance between neutralizing the attackers and getting as many people to safety as possible," he added.