Militants in Iraq linked to wanted terrorist Abu Musab al-Zarqawi say they have killed a second American hostage, and threatened the execution of the Briton, Kenneth Bigley, they are holding.
The militants announced the killing of Jack Hensley on the Internet Tuesday, but did not provide any evidence of the execution.
Monday, the militants released a video showing the beheading of the other American hostage, Eugene Armstrong.
The kidnappers demanded the release of women prisoners held by coalition forces in Iraq.
U.S. officials say they are holding two high-level female scientists associated with the ousted Iraqi regime.
News reports from Baghdad quoted Iraqi Justice Ministry officials as saying one scientist could be freed as part of a review of her detention. The officials insist the move is not related to the kidnappers' demand.