Nairobi (Agencies): At least fifteen people have died in militants’ attack on an upmarket hotel complex in Nairobi, according to Kenyan police sources.
It comes as fresh explosions and gunfire rang out in the siege which stretched into its second day.
Security forces worked throughout the night to secure the Dusit D2 compound, which includes a 101-room hotel, spa, restaurant and office buildings, after an attack claimed by Al-Shabaab militants yesterday afternoon.
At least one suicide bomber blew himself up at the hotel while gunmen sprayed fire before engaging security forces and holing themselves up at the premises as civilians fled or barricaded themselves in their offices awaiting rescue.
"We have 15 people dead as of now and that includes foreigners," a police source told a foreign news agency.
Among the dead was an American citizen, a State Department official said.
A second police source confirmed the toll but warned "there are areas not yet accessed but that's what we know so far".
After 12 hours trapped inside the complex, a group of dozens of people was freed at 3.30am local time, according to a journalist working for a foreign news agency at the scene, followed by fresh gunfire and a detonation.
"We still believe there are two or three attackers in specific locations," the first police officer said.
"The situation is far from over."
The second police officer said that at one point they had been sure the attackers had been neutralised after a long period without shooting, however gunfire resumed again after 2am.
Further explosions and gunfire were heard shortly before dawn, with no official word on how many people were still trapped inside.
"There is a floor where they are shooting from, we still believe there are people there," he said, after reports that a large number of people had fled upstairs.
Kenyan police chief Joseph Boinnet said the attack began with an explosion targeting three cars in the parking lot and a suicide bombing in the foyer of the Dusit hotel.
As the explosion and gunfire rang out in the leafy Westlands suburb, hundreds of terrified office workers barricaded themselves in the complex while some fled.
"We have no idea what is happening. Gunshots are coming from multiple directions," said an employee at an international firm who was hiding with his colleagues.
He was among a first wave of people evacuated from the office buildings surrounding the Dusit hotel, after an hour of sustained gunfire.
A number of heavily-armed foreign forces, who appeared to be from embassies based in Nairobi, were at the scene alongside Kenyan security officers.
One survivor rescued from the building told a local television station the attackers were "very confident; they were people who knew what they were doing".
CCTV footage broadcast on television showed four attackers, clad all in black and heavily armed, entering a courtyard in the compound at the start of the assault.
The attack was claimed by the Al-Qaeda-linked Somali group Al-Shabaab, which has repeatedly targeted Kenya since it sent its army into Somalia in October 2011 to fight the jihadist group.
The attack at Dusit D2 is the first in Nairobi since gunmen stormed the city's Westgate shopping mall in 2013, killing at least 67 people.