(CNN) — Gunmen attacked an upscale shopping mall in the Kenyan capital on Saturday, leading to a fierce gunbattle with police and leaving at least 20 people dead, the Kenyan Red Cross said.
Fifty more people were wounded in the attack at the mall in Nairobi, said Abbas Gullet, head of the Kenyan Red Cross.
A security agent told CNN’s Lillian Leposo at the scene that the violence was a terrorist attack, but officials had yet to confirm that information, Leposo told CNN.
“They have strong reason that these men are terrorists,” Leposo said.
The gunmen shot one person inside his car and two more people on the street as they entered the mall area, Leposo said.
Confusion continued about the origin of the gunmen, Leposo said. The attackers appeared to be of Somali origin, a Kenyan government source and Western diplomatic sources told CNN. But Leposo said there were reports that the gunmen were wearing masks, obscuring any identification.
Meanwhile, the army was mobilized to the mall, and two armored vehicles and an army helicopter joined police as both agencies were trying to secure the four-story mall floor by floor, Leposo said.
As distressed people are pulled out of the mall, they are surrounded by heavy security and are able to speak with family and authorities only, Leposo said.
The gunmen burst into the mall and shot indiscriminately, taking some people hostage, according to a senior Kenyan government source.
Several hours into the seige, gunshots inside the mall could still be heard by people outside the mall at about 10:30 a.m. Eastern, Leposo said.
Two years ago, there was a security alert sent the ex-patriot community to avoid the high-end mall because of reports of a planned attack at the mall, Leposo said.
One witness Saturday recounted the outburst of bullets inside the mall.
“All of a sudden we heard some shots and people rushing,” said Zulobia Kassam, who was having coffee at the mall. “We realized we were under attack. We rushed to the back, trying to hide and we heard random shots from everywhere — upstairs, downstairs.”
She said they stayed in hiding for about 40 minutes before sneaking out through a back door.
“People were petrified, crying, praying,” she said. “We were told there were hostages being held.”
It was unclear how many hostages the attackers took, but police are trying to negotiate for their release and retake the building, according to the source.
Crowds dashed down the streets as soldiers in military fatigues crawled under cars to get closer to the mall, guns cocked.
Surveillance helicopters flew overhead.
Police took those rescued from the building to a secluded place for vetting to ensure they were not attackers. They streamed away from the mall in a straight line, arms raised up in the air.
The military asked local media not to televise anything live because the gunmen are watching the screens in the mall.
“We urge Kenyans to keep off Westgate mall, adjacent roads and its environs until further notice,” the interior ministry said in a statement.
“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.”
Authorities said 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.
Village Market, another shopping center frequented by foreigners, shut down for the day as a precaution.
CNN’s Nima Elbagir and Boriana Milanova contributed to this report. Zulobia Kassam, a witness quoted in this story, is related to CNN’s Zain Verjee.