(CNN) -- A spokesman for the Kenya Defense Forces has identified four terrorists who took part in the deadly Nairobi mall attack last month.
They are: Khattab al-Kene, an American Somali; Abu Baara al-Sudani, from Sudan; Omar Nabhan, from Kenya; and a man identified only as Umayr.
The four died when the part of the mall they were in collapsed, Maj. Emmanuel Chirchir said.
The charred bodies of the four are undergoing DNA verification, Chirchir said.
No further details were immediately available. It was not clear what Khattab al-Kene's name may have been in the United States.
Throughout the four-day attack at the Westgate mall, it was unclear how many perpetrators were involved.
On Day Two, Kenyan authorities said between 10 and 15 attackers were involved.
The Islamic militant group Al-Shabaab claimed responsibility. Sources within the group said as many as three attackers were from the United States, two were from Somalia, and the others were one each from Canada, Finland, Kenya and the United Kingdom.
Kenya's Foreign Minister Amina Mohamed told PBS "NewsHour" that the attackers came from Kenya, the UK and the U.S.
"The Americans, from the information we have, are young men, about between maybe 18 and 19."
They are of Somali origin, but lived in Minnesota or other parts of the United States, she said, adding that underlines "the global nature of this war that we're fighting."
On Day Four, as the operation wound down, Kenya's President Uhuru Kenyatta said five terrorists were killed by Kenyan forces. Eleven others were in custody, he said, suspected of links to the attacks.