- NEW: Gunmen shoot indiscriminately and take some people hostage, sources say
- Police surround the mall in Nairobi and urge crowds to stay away
- "We're doing our job to ensure that everyone is evacuated to safety," interior ministry says
(CNN) -- Gunmen ambushed an upscale shopping mall in the Kenyan capital on Saturday, leading to a fierce gunbattle with police, witnesses said.
The gunmen shot indiscriminately and took some people hostage, a senior Kenyan source said. At least three people were injured by gunshots, the Kenyan Red Cross said.
It was unclear how many hostages they took, but police are trying to negotiate for their release and retake the building, according to the source.
Police surrounded the mall in the capital of Nairobi and warned crowds to avoid the area.
"We urge Kenyans to keep off Westgate mall, adjacent roads and its environs until further notice," the Interior Ministry said on its Twitter page.
It declined to release further information, saying it will issue a statement later.
"We're doing our job to ensure that everyone is evacuated to safety," the ministry said. "This is a scene of crime, let police do their job."
CNN affiliate NTV reported multiple shooters were at the scene and terrified shoppers were hiding inside the mall, which is popular among expatriates and the wealthy.
The high-end mall opened six years ago, and has more than 80 stores.
CNN's Nima Elbagir and Lilian Leposo contributed to this report from Nairobi
