A group called the Qaeda al Jihad in the Arabian Peninsula on Tuesday claimed responsibility for the attack on the US consulate in Jeddah, Saudi Arabia.
Five employees of the consulate and four attackers were killed in Monday's attack.
The claim of responsibility was posted on several Islamic Web sites.
In the Internet post, the group said, "This operation comes as part of several operations that are organised and planned by Al Qaeda as part of the battle against the crusaders and the Jews, as well as part of the plan to force the unbelievers to leave the Arabian Peninsula."
It said the fighters killed nine employees of the consulate, including two Americans, and seven Saudi soldiers.
The US embassy said no Americans were killed or seriously injured.
However, a Saudi official said in Washington, DC said members of the Al Fallujah Brigade had carried out the attack.
Adel Al Jubeir, foreign affairs advisor to Saudi Crown Prince Abdullah bin Abdul Aziz, said the gunmen made the claim in a call to the authorities shortly after attacking the consulate.