WASHINGTON – Defense Secretary Leon Panetta said Wednesday the U.S. "will take all necessary and proper steps" to deal with an Islamist attack on a natural gas field in southern Algeria that has resulted in Americans and other foreigners taken hostage.

Panetta would not detail what such steps might be, but he condemned the incident as "terrorist attack" and likened it to al-Qaida activities in Pakistan, Afghanistan and in the United States on 9/11.

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. Panetta said he didn't know the numbers of those kidnapped.