An Islamic Web site on Monday showed the beheading of two hostages, one a Turkish contractor and the other an Iraqi Kurdish translator wearing a badge of the Titan security company.
A statement said the two were killed by the Ansar al-Sunnah Army, which also claimed responsibility for slaughtering 12 Nepalese workers and three Iraqi Kurds on Aug. 31.
Also Monday, the Arabic language television station Al-Arabiya broadcast a video showing three hooded gunmen threatening to behead another Turkish hostage within three days unless the Americans release all Iraqi prisoners and all Turks leave Iraq.
A written statement appearing on the video showing the beheadings accused the Kurdish translator of participating in raids with U.S. troops in the Ramadi area. A second statement claimed the Turkish contractor was working for the Americans at an air base north of the capital.
The Kurdish hostage identified himself as Luqman Hussein and said he worked with U.S. forces at an agricultural site in Ramadi. He said he was captured en route to Baghdad, about 70 miles east of Ramadi.
The tape did not say where the Turk was captured.
The videotape warned foreigners against coming to Iraq "for making cheap earthly profits by being allies with the Crusaders in their war on Islam."
The tape broadcast by Al-Arabiya television showed three gunmen standing behind a hostage said to be a Turkish truck driver. One of the gunmen identified the kidnappers as members of Tawhid and Jihad, Iraq's most feared terror group that has been responsible for beheading several foreign hostages in Iraq.
However, the tape did not feature the group's banner, which has always appeared in Tawhid and Jihad video statements.
"We of the group of Tawhid and Jihad announce, that we will cut off the head of this hostage if our demands are not met," the speaker said as the hostage's eyes darted from one side to another. "We have long warned them not to enter the land of Islam and land of Jihad, the land of Iraq."
The video showed the hostage's passport but the name could not be determined.
Insurgents in Iraq have kidnapped more than 150 foreigners in their campaign to drive out coalition forces and hamper reconstruction. Most have been kidnapped for ransom and freed unharmed, but at least 28 have been killed by their abductors.