UPDATE: Death toll from Nairobi attack rises to 21 and 50 unaccounted for
At least 15 people were killed in an attack on an upscale hotel and office complex in the Kenyan capital Nairobi on Tuesday afternoon.
Somali militant group Al Shabab claimed responsibility for the attack. The Al Qaeda-linked group claimed the attack via its radio arm, Andalus.
"We are behind the attack in Nairobi. The operation is going on. We shall give details later," said Abdiasis Abu Musab, Al Shabab's military operations spokesman.
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Multiple attackers, wearing green and wrapped in ammunition, stormed the DusitD2 complex in the neighbourhood of Westlands, sending office workers fleeing for their lives.
Kenya's national police chief said the co-ordinated attack on the hotel began with an explosion that targeted three vehicles outside a bank while a suicide bomber blew up in the hotel lobby.
According to a mortuary worker who spoke to Reuters, the dead included 11 Kenyans, an American and a Briton.
The bodies were identified based on identification documents on them when they arrived at Chiromo mortuary, said the attendant.
A Somali diplomat said Somalian officials were in a Nairobi hotel for meetings at the time it was attacked on Tuesday and several are feared to still be inside. The diplomat spoke on condition of anonymity because they were not authorised to speak to reporters.
As night fell, gunfire continued more than two hours after the first shots were heard at the complex. Police later said they have secured most of the building.
A plume of smoke rose above the 14 Riverside Drive complex. Firefighters extinguished three cars ablaze by the entrance as armed security personnel headed in and other armed officers escorted shocked workers out, many with their hands up.
Police said they detonated a car with explosives inside. The blast sent people at the scene ducking and screaming.
A woman shot in the leg was carried out and three men emerged covered in blood. Some office workers climbed out of windows.
Several vehicles were seen burning and people were being rushed and carried from the scene.
"We are under attack," another person in an office inside a complex in the Dusit hotel told Reuters, before hanging up. Local television showed smoke rising from the area.
The complex includes the DusitD2 hotel, banks and offices.
Several social media users reported being trapped in the building and nearby offices as surrounded buildings were being evacuated.
A police team from the General Service Unit, the highly-trained paramilitary wing of the Kenyan police force, were dispatched to the affluent neighbourhood of Westlands in northern Nairobi after the gunshots were heard, according to local media reports.
Police initially said it could have been a robbery but later said they were not ruling out a militant attack.
"We have to go for the highest incident that could take place. The highest incident we have is a terror (attack)," spokesman Charles Owino told Citizen TV.
They then confirmed what it said was an "attack incident" on Twitter.
What appeared to be plainclothes security forces were seen inching their way toward the scene, guns in hand. Other people took cover behind fountains and other features in the lush outdoor complex.
Some of those who appeared to have been rescued from the complex tweeted their relief. "We have been rescued," said one Kenyan. "Thank you for your prayers."
The attack is similar to a reminder of the Westgate Mall attack in Nairobi in 2013, when Al Shabab extremists burst into the luxury shopping center, hurling grenades and starting a days-long siege that left 67 people dead.
Tuesday's attack came a day after a magistrate ruled that three men must stand trial on charges they were involved in the Westgate Mall siege. A fourth suspect was freed for lack of evidence.