© Ben Curtis/Associated PressSecurity forces help civilians flee the scene as cars burn behind at a hotel complex in Nairobi Tuesday.
Extremists initially attacked a luxury hotel Tuesday afternoon local time, sending people fleeing in panic as explosions and heavy gunfire reverberated through the complex and black smoke rose over the scene.
Surveillance video showed three attackers dressed in black running across the parking lot at 3:30 p.m., shortly followed by a fourth. At least two of the men were wearing green scarves in the close-up footage. One appeared to be wearing a green belt with grenades on it.
Al-Shabaab - the Somalia-based extremist group that carried out the 2013 Westgate Mall attack in Nairobi that left 67 people dead - claimed responsibility.
© Security Camera Footage/Associated PressIn this grab taken from security camera footage released to the local media, heavily armed attackers walk in the compound of a Nairobi hotel Tuesday.
The co-ordinated assault began with an explosion that targeted three vehicles outside a bank, and a suicide bombing in the hotel lobby that severely wounded a number of guests, said Kenya's national police chief, Joseph Boinnet.
© Thomas Mukoya/ReutersCars are seen on fire at the scene of explosions and gunshots in Nairobi on Tuesday.
"I would like to reiterate that the situation is under control and the country is safe," he said.
But into the early hours of Wednesday local time, gunfire could still be heard as authorities evacuated about 150 survivors from the buildings, according to a first responder, who said a pregnant woman and the daughter of a former Kenyan politician were among them.
He said many more wounded remained trapped inside.
© Ben Curtis/Associated PressCivilians who had been hiding in buildings flee under the direction of a member of security forces.
A U.S. State Department official confirmed one of the victims was American.
Kenyan authorities have not yet announced whether the attackers are dead, detained or on the run.
© Security Camera Footage/Associated PressSecurity camera footage released to the local media showed an armed attacker walking in the notel compound. Al-Shabab, the Somalia-based extremist group, is claiming responsibility.
A witness who gave his name only as Ken said he saw five bodies at the hotel entrance during the attack. He said that other people were shouting for help and "when we rushed back to try to rescue them, gunshots started coming from upstairs, and we had to duck, because they were targeting us and we could see two guys shooting."
Kenyan hospitals appealed for blood donations even as the number of wounded remained unclear.
'Quite nerve-racking'
The complex includes the DusitD2 hotel, along with bars, restaurants, banks and offices and is in a well-to-do neighborhood with large numbers of American, European and Indian expatriates.
© Ben Curtis/Associated PressSecurity forces point their weapons through a shattered door behind which an unexploded grenade lies.
They couldn't see anything, because they were on the side of the building facing away from the chaos.
"You'd hear footsteps above, you'd hear other things, other people moving around in the building," said Crump.
"And it's quite nerve-racking, because you just don't know whether the noises you're hearing, whether it's people, whether it's police, whether it's terrorists, you just don't know what those noises are."
Other survivors closer to the where the attackers rampaged reported hearing a shattering blast and saw people mowed down by gunmen as they sat at a cafe. Victims were left lying on tables, bleeding.
© Ben Curtis/Associated PressCivilians flee the scene after terrorists attacked an upscale hotel complex in Kenya's capital Tuesday, sending people fleeing in panic as explosions and heavy gunfire reverberated through the neighbourhood.
Associated Press video from inside the hotel showed Kenyan security officers anxiously searching the building and scared workers emerging from hiding while gunfire could still be heard. Some women climbed out of windows. One man got up from the floor where he appeared to be trying to hide under a piece of wood paneling, then showed his ID badge.
As officers searched luxury fashion displays, wounded people were carried away on stretchers.
Anniversary of military base attack
Gunfire continued several minutes after the first reports as ambulances, security forces and firefighters converged on the scene. A bomb disposal unit arrived, and vehicles were cordoned off for fear they contained explosives.
Police said they blew up a car that had explosives inside. An unexploded grenade was also seen in a hallway at the complex.
Crump said gunfire could still be heard as him and his colleagues eventually evacuated.
"I don't know where those shots were coming from or who they were coming from, but as we were leaving it was definitely still much still very much active shooters around," he said.
Al-Shabaab has vowed retribution against Kenya for sending troops to Somalia since 2011. The al-Qaeda-linked group has killed hundreds of people in Kenya, which has been targeted more than any other of the six countries providing troops to an African Union force in Somalia.
© Baz Ratner/ReutersMembers of security forces secure a building at the scene in Nairobi.
"I've been here five years, and obviously you're aware of the security issues and the fact that hotels and corporate office blocks and shopping centres are high targets, but I think we've had a false sense of security," said Crump.
On Monday, 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.
The attack on Tuesday came three years to the day after al-Shabaab extremists attacked a Kenyan military base in neighbouring Somalia, killing scores of people.
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