Authorities investigating last month's deadly attack at a Kenyan mall have identified a Norwegian-Somali man as a suspect.

Security officials say investigators are trying to determine if 23-year-old Hassan Abdi Dhuhulow was one of the gunmen who took part in the siege that killed at least 67 people, not including the attackers.

News reports indicate that Dhuhulow was identified on surveillance video from the Westgate Mall.

Dhuhulow was born in Somalia but his family later moved to Norway. It is not clear if he is still alive.

Kenyan authorities previously released the names of four other militants they say were involved the attack, all of whom were killed.

Gunmen stormed the Westgate Mall on September 21, killing scores of people and setting off a standoff with security forces that lasted for four days.

Investigators continue to gather evidence at the mall, which partially collapsed during the siege. On Friday, Kenyan officials said investigators had recovered charred remains which may be the bodies of two of the gunmen.

Al-Shabab has vowed to carry out other acts of violence against Kenya. The rebel group is demanding that Kenyan forces withdraw from Somalia.

Kenya sent troops to Somalia two years ago to help battle al-Shabab, which has been fighting to turn Somalia into a strict Islamic state.