CAIRO, Egypt - A videotape that was posted Wednesday on Islamic Web site showed militants affiliated to wanted Jordanian terrorist Abu Musab al-Zarqawi beheading two Iraqis purported to be intelligence officers.

The 10-minute tape showed two captives, Fadhel Ibrahim and Firas Imeil, identifying themselves as Iraqi National Intelligence officers and saying they were captured in Baghdad's Haifa Street on Sept. 28.

In separate scenes, the tape showed four masked gunmen standing behind Ibrahim and then Imeil, with one militant describing the blindfolded captives as "criminals."

There was no way to immediately verify the authenticity of the tape, which was released in the name of the Brigades of Abu Bakr Al-Sidiq, a militant group affiliated to al-Zarqawi's Tawhid and Jihad organization.

Al-Zarqawi's group has kidnapped and beheaded numerous foreigners in attacks aimed at driving foreigners out of Iraq.

The militant speaking in the tape mentioned the recent U.S.-led attacks against militants in the Iraqi city of Samarra and appeared to acknowledge a setback for insurgents in the city.

"Let America and those behind it know that what had happened in Samarra was a mere labor pain," the militant said, adding that "war has its ups and downs." U.S. and Iraqi troops claimed success earlier this month when they swept into Samarra, an insurgent stronghold northwest of Baghdad.

"It is a disgrace that such a criminal is considered as a member of our nation," the militant said. Then two other masked men held down Ibrahim and a third severed the captive's head with a knife before holding it up to the camera.

Imeil, who said he joined the Iraqi intelligence services four months ago and attended a training course in Jordan, was killed in identical fashion.

Before being beheaded, both victims advised fellow Iraqis working in the intelligence, police, national guard and other services to quit their jobs and "repent to God."