The British man arrested earlier in the week at Jomo Kenyatta International Airport has been identified as Mohammed Abdilazak.
Abdilazak, 35, was arrested while walking around inside the airport after being cleared to fly to London.
Police became suspicious of him after realizing he had a wrong boarding pass, and suspected the passport he was carrying was fake, reported The Star, a Kenyan news agency.
Police were also suspicious because the man had bruises on his face, and was wearing dark glasses, reported the Daily Mail.
The man missed his flight at 3 p.m., increasing the suspicion, but he told police that he missed it by accident,and his passport is genuine.
He also said that he had nothing to do with the Westgate attack, or the attack on the Nairobi mall by armed militants that has left at least 72 dead and hundreds wounded.
Abdilazak came into the country in June, investigators said. He said he came to visit his mother.
Abdilazak was still in custody as of Tuesday night.
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