The Pentagon said Friday it is withdrawing service members' families and nonessential personnel from Bahrain (search) for at least 30 days in response to information of planned terrorists attacks in the tiny Persian Gulf nation.

The relocation is mandatory, and the Pentagon also is suspending travel to Bahrain for all other personnel.

The State Department, in an advisory Thursday, cautioned Americans against traveling to Bahrain and advised Americans who live there to leave. The warning did not elaborate on the reported threats except to say terrorists were at large and the information was credible.

"We are aware of the State Department advisory which says they have received information that extremists are planning attacks against U.S. and other Western interests in the Kingdom of Bahrain," the Pentagon said in a written statement Friday evening.

"Credible information indicates that extremists remain at large and are planning attacks in Bahrain. In neighboring Saudi Arabia, for example, terrorists have targeted residential housing compounds using vehicle bombs, resulting in numerous deaths and injuries, including American citizens."

The Pentagon said the decision to withdraw was made by Defense Secretary Donald H. Rumsfeld at the recommendations of Gen. John Abizaid (search), the Central Command commander who is responsible for military operations in the Persian Gulf region, and of Gen. Richard Myers, chairman of the Joint Chiefs of Staff.

Last month, the Bahrain government released six men after their detention on suspicion of plotting terror attacks.

The Pentagon statement made no mention of the release of the six, but officials were known to be displeased at the Bahrain government's handling of some detainess.

Bahrain has stepped up security on a 15-mile causeway that links the country to Saudi Arabia.

"The threat of terrorism is very real," State Department spokesman Adam Ereli said Friday. "We are working with the (Bahraini) government."

Roughly 80 families of U.S. military personnel live in Bahrain, military officials said. They will be brought to unspecified locations in the continental United States, the Pentagon statement said. They will not be allowed to return to Bahrain until the mandatory withdrawal order is terminated.

Bahrain is home to the Navy's 5th Fleet (search), which operates in the Persian Gulf.