According to Channel 4 News in UK, the alleged leader of the Nairobi shopping mall attack was born a Christian in Kenya and is a former member of the country's special forces.
The number one Westgate attacker was named as Omar or Umayr, who is believed to have been killed in this week's siege.
Omar was a Kenyan national, born to a Christian family from Nairobi. He converted to Islam and was also a former member of Kenya's special forces.
Umayr is understood to have left Kenya for Somalia in 2005, where he joined the Kamboni militant Islamist group. Kamboni later joined with al-Shabaab.
The report said the second man is known as Khadhab, who is a Somali national who worked in an Islamic bookshop in the Nairobi suburb of Eastleigh. He was arrested and imprisoned in Somalia, and it is alleged he was tortured by the CIA while in custody there.
The Kenyan government has not given any details of the identities of the Westgate mall attackers.
Al Shabab militant group who claimed the attack did not reveal any of the identities of the Nairobi attack which killed more than 70 people.
Sixty-seven people are confirmed dead following the four-day siege, but that death toll is expected to rise.