The Obama administration is condemning an Islamist attack on a natural gas field in southern Algeria and confirming that Americans are among those being held hostage.
Defense Secretary Leon Panetta told reporters in Italy that Americans were among the hostages and called the incident a "terrorist attack."
A militant group that claimed responsibility says it's holding seven Americans, but State Department spokeswoman Victoria Nuland said she wouldn't provide details to protect those who were kidnapped.
Militants said they attacked and occupied the field partly operated by the energy company BP because of Algeria's support of France's operation against al-Qaida-linked Malian rebels groups to the southeast.
Nuland said Secretary of State Hillary Rodham Clinton spoke Tuesday by telephone with Algerian Prime Minister Abdelmalek Sellal.
U.S. authorities also were in contact with BP.