Members of the Abu Musab al-Zarqawi insurgent group in Iraq have posted a video of the beheading of American hostage Eugene Armstrong on an Islamist website. The group, who had demanded over the weekend that Muslim women be released from Iraqi prisons, has given the US a new 24-hour deadline to comply or more hostages - another American and a Briton - will be killed.

The US claims there are no women being held at the Umm Qasr or Abu Ghraib US-controlled prisons. However, two female "high-value detainees" who were former members of Saddam Hussein's regime (including Dr. Rihab Rashid Taha, a scientist who became known as "Dr. Germ" for helping Iraq make weapons out of anthrax) are being held at undisclosed locations. CNN has more.