Kenyan security forces said Tuesday they are in the final push to reclaim control of an upscale mall in Nairobi, which for four days has been under siege by a multinational group of al-Qaida-linked extremists.
The Associated Press cites an anonymous source who says there are still some remaining hostages inside the Westgate Mall, though government officials say most have been released. It is unclear how many militants from the Somali-based al-Shabab extremist group are still holed up.
Kenyan authorities say 62 people died in the attack.
The FBI is looking into claims that Westerners were among the attackers, which Kenyan Foreign Minister Amina Mohamed says included Americans and at least one Brit.
"The Americans, from the information we have, are young men, about between maybe 18 and 19," she told "PBS NewsHour" in an interview, adding that the British suspect, a woman, has "done this many times before."
The U.S. suspects are of Somali or Arab origin and lived in Minnesota "and one other place," Mohamed said.
"That just was to underline, I think, the global nature of this war that we're fighting," she said.
"These people who perpetrate these crimes didn't fall from outer space," Mohamed added. "They live among us. They live in our countries. Right? We know them."
Security officials in Kenya believe there were at least 30 hostages as of Saturday. Initial reports indicated that the militants allowed shoppers in the mall to leave if they could prove they are Muslim.
Explosions and gunfire rang out Monday morning as billowing smoke rose from the site of the mall. Evacuating the hostages went "very, very well," said Kenyan Interior Minister Joseph Ole Lenku. Officials are 'very certain" that few, if any, hostages remain in the building.
Kenyan officials also made such claims on Sunday.
President Barack Obama said Monday he had spoken with Kenyan President Uhuru Kenyatta, whose nephew is among those killed in the attack on the mall, and called the attack "a terrible tragedy."
"We are providing all the cooperation that we can as we deal with a situation that has captivated the world," Obama said from New York, where he and other world leaders have arrived for the annual U.N. General Assembly.
"We will provide them with whatever law enforcement support that is necessary," he said. "And we are confident that Kenya, which has been a pillar of stability in Eastern Africa, will rebuild."
Obama did not mention the allegations that Americans fought with the militants.
State Department spokesperson Jen Psaki said Monday that there was "no definitive evidence of the nationalities or the identities of the attackers."
Fox News reports the FBI and other U.S. intelligence services are "aggressively" investigating the claims that Americans were involved in the attack.