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At least three of the attackers responsible for a reign of terror on an upscale Kenyan mall, killing at least 68, are from the United States, CNN reports.
CNN's Sara Pratley, senior director of coverage at the news network, broke the news on Twitter Sunday afternoon. CNN also reported the news on television.
A State Department official confirmed to TheBlaze on Sunday they are looking into the report that individuals from the U.S. may have been involved in the attacks.
CNN says the nationalities of the attackers originated from a now-suspended Twitter account, where their sources confirmed nine names listed were among the alleged hostage takers.
Three of the alleged attackers are from the U.S., two are from Somalia and there is one each from Canada, Finland, Kenya and the United Kingdom, according to the list.
TheBlaze has viewed information and names from another Twitter account that surfaced once the original account was taken down, but so far those names are unconfirmed.
An FBI official told TheBlaze they are "unable to confirm whether or not any of the attackers are American," but added that they are investigating the matter.
An armed police officer takes cover during a bout of gunfire outside the Westgate Mall in Nairobi, Kenya Saturday, Sept. 21, 2013. Gunmen threw grenades and opened fire Saturday killing at least 22 people in an attack targeting non-Muslims at an upscale mall in Kenya's capital that was hosting a children's day event, a Red Cross official and witnesses said. (AP Photo/Ben Curtis)
Kenyan's military said late Sunday it had rescued "most" of the remaining hostages held by al-Qaida-linked militants in an upscale Nairobi mall after launching a major operation to end a two-day standoff that had already killed 68 people.
The assault, which began shortly before sundown, came as two helicopters circled the mall, with one skimming very close to the roof. A loud explosion rang out, far larger than any previous grenade blast or gunfire volley.
Kenya Defence Forces later said it had rescued most hostages and had taken control of most of the mall. Officials did not immediately release the number of hostages rescued or the number that remained. Four Kenyan military personnel were wounded in the operation, the military said.
Somalia's al-Qaida-linked rebel group, al-Shabab, claimed responsibility for the attack that specifically targeted non-Muslims. The attackers included some women. The Islamic extremist rebels said the attack was retribution for Kenyan forces' 2011 push into neighboring Somalia.
The Associated Press contributed to this report.
UPDATE, 7:30 PM ET -- 9/22:
Screenshots circulated widely on the Internet show that a suspected Al-Shabab twitter account, with the handle "@HSM_Press2," earlier tweeted out a list of individuals they say are involved in the Kenya mall attack.
That list included the names of three people the account claimed were from U.S. cities Saint Paul, Minneapolis and Kansas City.
That Twitter account was later suspended, but a U.S. official with direct knowledge of the terrorist organization confirmed to TheBlaze on Sunday evening the "@HSM_Press2" account was authentic.
A senior administration official told TheBlaze the administration cannot confirm reports that some of the attackers were Americans, but are seeking more details.
It was not immediately clear why the terrorist organization would allegedly out their own operatives by sending out names of individuals they say were involved in the attack.
TheBlaze has not been able to confirm the claims made by the account, but we are working to verify the information.
UPDATE, 11:00 PM ET -- 9/22:
BBC Africa is reporting Abu Omar, the Al-Shabab military commander in Somalia, has denied reports Americans are involved in the attack.
UPDATE, 8:20 AM ET -- 9/23:
Monday morning, CNN altered the language in their article.
Their original story said "sources within Al-Shabaab told CNN that nine names listed on a Twitter site -- now suspended -- were people who were among the alleged hostage takers." The article then said "three of the alleged attackers are from the United States."
On Monday, the article no longer cited "sources within Al-Shabaab."
"Before its Twitter account was suspended, Al-Shabaab issued a list of nine names it said were among the attackers. It said three were from the United States, two from Somalia and one each from Canada, Finland, Kenya and the United Kingdom," the article now reads.
This is a developing news story. Updates will be added.
Follow Oliver Darcy (@oliverdarcy) on Twitter