Washington ? An investigation into possible security breaches at the Guantanamo Bay prison camp for terror suspects has expanded to a third member of the military, Pentagon officials said Wednesday.

The arrests of an Air Force translator and a Muslim Army chaplain — both worked at the Cuban base and have apparent ties to Syria — have shaken Defense Department officials. About 660 suspected Taliban or al-Qaida members are being held at the high-security base.

“We don’t presume that the two we know about is all there is to it,” Gen. Peter Pace, vice chairman of the Joint Chiefs of Staff, told reporters.

A member of the Navy who was also part of the small military community at the Guantanamo Bay prison camp is under investigation in the security probe but has not been arrested, Pentagon officials said. They did not identify the service member.

So far, charges have been filed only against Senior Airman Ahmad I. al-Halabi, 24, who worked as an Arabic language translator for the detainees. He is accused of espionage, aiding the enemy, lying to investigators and charges that he tried to pass classified information about prisoners and base security to “the enemy” and to his native Syria. The most serious charges carry a possible death sentence.

Al-Halabi denies the charges, said his lawyer, Air Force Maj. James Key III. He is also accused of not reporting unauthorized contacts with the Syrian Embassy, but Key said those contacts were to arrange for a trip to Syria to get married. Al-Halabi had his plane ticket for that trip with him when he was arrested July 23 after arriving in Florida from Guantanamo Bay, Key said.

Syrian government spokesmen denied links to the airman, who was arrested in July, more than six weeks before the arrest of the chaplain, Army Capt. Yousef Yee, 35. Yee has not been charged but is being held in a Navy brig in Charleston, S.C., on suspicion of breaching Guantanamo Bay security.

Yee also has ties to Syria: He learned Arabic and studied Islam there for four years in the early 1990s. Al-Halabi lived in Syria at the time but he was still a boy; he traveled with his family to the Detroit area in 1996 and went to high school in a Detroit suburb.

The two men served at Guantanamo Bay at the same time and knew each other, though the extent of their relationship is unclear, said military officials and Key.

Senior law enforcement officials, speaking on condition of anonymity, said thus far there was no evidence of involvement by individuals in the United States who are not part of the U.S. military.

On Capitol Hill, meanwhile, Gen. Richard Myers, chairman of the Joint Chiefs of Staff, said security procedures at Guantanamo Bay were being reviewed.

“Any time you have allegations like this, you always look at your procedure and process,” Myers told reporters.