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.

Read more: Two Indians among 68 killed in Kenya terror attack
               
As troops ran into new positions, one security official said: "It is us who caused the explosion, we are trying to get in through the roof." He declined to be named. Military spokesman Colonel Cyrus Oguna declined comment when asked whether security forces had set off the detonations or whether militants had set off explosives inside the building.

A plume of oily black smoke was still pouring from the building after half an hour. 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 neutralising the attackers and getting as many people to safety as possible," he added.
               
A spokesman for al Shabaab, which has demanded Kenya pull its troops out of neighbouring Somalia, warned that they would kill hostages if Kenyan security forces, who are being assisted by Western and Israeli experts, tried to storm their positions. "Israelis and Kenyan forces have tried to enter Westgate by force but they could not," Sheikh Ali Mohamud Rage said in an audio statement posted online.
               
On Twitter, the group posted: "As the operation gathers momentum inside Westgate, the Mujahideen are for the 3rd day still in full control of the situation on the ground."
               
The Red Cross said on Monday that the death toll since Saturday's initial lunchtime bloodbath stood at 69. But Interior Minister Lenku said that was wrong and that only 59 were dead. The Red Cross also said it had also recorded 63 people being reported by relatives as missing.
               
Survivors' tales of the military-style assault by squads of attackers hurling grenades and spraying automatic fire, has left little doubt the hostage-takers are willing to kill. Previous raids around the world, including at a desert gas plan in Algeria nine months ago, suggest they are also ready to die.

Agencies (Video Courtesy: Mid-Day)

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