Emergency medical staff treated some of the wounded
near the building's entrance
A gun fight inside a shopping centre in the Kenyan capital Nairobi has left at least 10 people dead, eyewitnesses say.
Police say gunfire erupted as gunmen tried to rob a shop in the Westgate centre - one of the city's most exclusive shopping malls.
While dozens of shoppers fled, several people are still feared trapped inside.
Police told AFP that gunmen had taken at least seven people hostage. Officers have now surrounded the building in an attempt to evacuate remaining shoppers.
At least four people have also been wounded in the attack. While officials have not yet confirmed the death toll, Associated Press reporters at the scene said they counted up to 10 bodies.
Eyewitnesses say masked attackers threw grenades into the building at about midday local time (09:00 GMT).
Nairobi police chief Benson Kibue told AP news agency that the gunmen had been trying to rob a shop within the mall when the shooting began.
Security forces have surrounded the shopping centre
Arjen Westra, who was drinking coffee at the time of the attack, told the BBC he thought the cafe he was in was being targeted by the gunmen.
"I could hear the gunfire moving towards the main entrance of the shopping mall, so some people ran out of our cafe in a kind of panic, and quite a number just fell down as flat as possible on the ground."
Security guards used shopping trolleys to wheel out several wounded children and at least one man, AP reports.
"The gunmen tried to fire at my head but missed. There are definitely many casualties," Sudjar Singh, who works at the shopping centre, told AFP.
"I saw three of the attackers dressed in black and with covered faces and they were carrying heavy rifles," said another witness.
Dozens of shoppers were given assistance in evacuating the area
Children and families were taken to safety after the shootings began
One Nairobi resident, Anupa, who lives near the scene, told the BBC: "I heard the exchange of fire when it happened, and I heard what I thought was a grenade, but I didn't go outside. The whole area is cordoned off."
Armed police took cover behind vehicles outside. "We have officers at the scene trying to get out the group shooting inside," a police official told AFP news agency.
"Officers are approaching the situation with caution because there are innocent civilians inside," he said.
The Westgate centre is often frequented by wealthy Kenyans and expatriates. Police have urged residents to stay away from the area.