Al shabaab now claim they are behind the attack at 14 Riverside Drive, Nairobi on Tuesday.

According to Al Jazeera, the militia group’s military operations spokesman said: “We are currently conducting an operation in Nairobi.”

Reuters identified the man as Abdiasis Abu Musab.

“We are behind the attack in Nairobi. The operation is going on. We shall give details later,” he said.

Security agencies told Citizen TV’s Francis Gachuri that they had spotted six gunmen at the Riverside complex.

A fire and sustained gunfire sent workers fleeing for their lives at the upscale hotel and office complex, witnesses told Reuters.

One man came out covered in blood as students were evacuated from the nearby Nairobi University Chiromo campus.

“I just started hearing gunshots, and then started seeing people running away raising their hands up and some were entering the bank to hide for their lives,” a woman working in a bank near the hotel said.

She also heard two explosions.

“We are under attack,” another person in an office inside the complex told Reuters, then hung up. A large plume of smoke could be seen rising from the area.

Four ambulances and a fire truck arrived at the scene as fleeing office workers told Reuters colleagues were still huddled under their desks.

Three cars were ablaze at the entrance and a picture of the hotel grounds on Twitter showed what appeared to be a human a leg lying on the path.

Nairobi police commander Philip Ndolo said they had cordoned off the area around Riverside Drive and urged motorists to find alternative routes.

Report from Al Jazeera and Reuters

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