Yet another military member is being questioned about security violations at a U.S. prison camp, adding to a probe which already includes the arrests of Ahmad I. al-Halabi (search), the Syrian-born Air Force airman accused of espionage, and a U.S. Army Muslim chaplain, Pentagon officials said Wednesday.
Military investigators also were looking Wednesday for links between al-Halabi and the chaplain, who has personal ties to Syria and is being held in detention.
One suspect, a member of the Navy, is under investigation but has not been arrested, Pentagon officials said.
The cases have raised concern in the Defense Department about security at the Guantanamo Bay Naval Base (search) in Cuba, said Gen. Peter Pace, vice chairman of the Joint Chiefs of Staff.
"We don't presume that the two we know about is all there is to it," Pace told reporters Wednesday morning.
The U.S. military was also searching for other service members who may be part of a suspected espionage ring operating at Guantanamo Bay, where about 660 suspected Al Qaeda (search) and Taliban (search) members are currently imprisoned.
Pentagon officials told Fox News more arrests could be made soon.
Al-Halabi, an Arabic-language translator at Guantanamo, has been accused of trying to send information about detainees to Syria. He has been charged with espionage and aiding the enemy and could face execution.
Al-Halabi knew Yousef Yee (search ), the chaplain whose arrest earlier this month was announced Saturday, and who studied in Syria and married a Syrian woman.
A military magistrate ruled on Sept. 15 that there was enough evidence to hold Yee for up to two months on suspicion of espionage during the investigation, but no charges have been filed. Yee was carrying sketches of the prison and documents about detainees and interrogators at the time of his arrest.
"I think it sends a pretty clear message to the rest of the folks there that we're pretty serious about safeguarding the activities that go on there," retired military intelligence officer John Nolan told Fox News.
Sen. Richard Shelby, R-Ala., told Fox News that the situation was potentially dangerous. "They’ve got to look at everybody down there, who's interrogating who, who has access to this type of information … where there is sympathy for the terrorism and where that is prevalent, we've got to root that out," Shelby said.
The arrests raise new questions about Syria's motives and actions in the U.S. campaign against Islamic fundamentalist terrorism.
Syria is on the State Department's list of countries sponsoring terrorism, but Washington and Damascus have long had normal diplomatic relations and Syria was forthcoming with intelligence about Al Qaeda after the Sept. 11 terror attacks.
Defense Secretary Donald Rumsfeld and other administration officials have accused Syria of possessing chemical weapons - unlike Iraq, it never signed anti-chemical weapon agreements - and of helping Saddam Hussein's regime before and during the recent Iraq war.
Rumsfeld has also said Syrian nationals make up the largest number of foreign fighters captured in Iraq since the end of major combat. Damascus has denied both accusations.
Syrian Information Minister Ahmad al-Hassan on Wednesday said that reports linking Syria to the potential spies were "baseless and illogical."
Lebanon's top Shi'ite Muslim cleric, Sheikh Mohammed Hussein Fadlallah, struck out at Washington's Syrian policy.
"America speaks to Syria like a dictator speaks to its subjects," he said at his weekly roundtable, Reuters reported.
The Case Against Al-Halabi
The military charges al-Halabi with sending e-mails with classified information "to unauthorized person or persons whom he, the accused, knew to be the enemy." That enemy is not specified.
A military attorney representing al-Halabi, Air Force Maj. James E. Key III, told The Washington Post: "Airman al-Halabi is not a spy and he is not a terrorist."
Al-Halabi, 24, who joined the Air Force in January 2000, is also accused of lying to the Air Force by falsely claiming to have become a naturalized U.S. citizen in 2001. He has applied for citizenship, but it has not yet been granted.
He grew up in Detroit and is being held at Vandenberg Air Force Base in California.
In total, Al-Halabi is charged with eight counts related to espionage, three counts of aiding the enemy, 11 counts of disobeying a lawful order, nine counts of making a false official statement and one count of bank fraud. The charges include an allegation that al-Halabi failed to report unauthorized contacts between prisoners and other military members.
He is accused of trying to pass to Syria details of flights to and from Guantanamo Bay, names, serial numbers and cell numbers of prisoners, a map of the base and other military documents.
Al-Halabi worked for nine months at Guantanamo, and was rotating back to the U.S. mainland when he was arrested July 23 in Jacksonville, Fla., after getting off a flight from the Cuban base.
He was carrying two handwritten notes from detainees that he intended to turn over to someone traveling to Syria, the charging documents say. He was also carrying his personal laptop computer, which contained classified information about detainees and 180 messages from detainees al-Halabi intended to send to Syria or Qatar, they said.
A Pentagon official told Fox News that slip-ups such as the laptop containing classified information - which he described as "sloppy computer security" - are somewhat common.
Al-Halabi is also accused of taking pictures of the prison camp and having unauthorized contact with the inmates, including giving them baklava desserts. The documents allege he had contacts with the Syrian Embassy to the United States, which he failed to report.
Espionage and aiding the enemy are military charges that can carry the death penalty, said Eugene Fidell, a civilian lawyer in Washington and president of the National Institute of Military Justice. The commanding general in charge of al-Halabi's case would have to decide whether to seek the death penalty, Fidell said.
Air Force officials also haven't decided whether al-Halabi's case will be handled by a court-martial.
The last military execution was in 1961, Fidell said.
Al-Halabi was based at Travis Air Force Base in California and assigned to a logistics unit there.
"He loved being in the U.S.," a family friend told The Washington Post. "He said, 'I have a dream life here.'"
The friend also said the Halabi family keeps its distance from the Syrian government, currently headed by Bashar al-Assad, son of longtime dictator Hafez al-Assad.
"Definitely, Ahmad has no political interest whatsoever," the friend added.
Investigating the Chaplain
Yee, a West Point graduate, was arrested Sept. 10 and is being held at a Navy brig in Charleston, S.C. He was detained in part because he carried classified information without having something called a "courier card" in his possession. He also had a laptop equipped with a modem, which are strictly forbidden at the base.
Meanwhile, Sen. Charles Schumer, D-N.Y., criticized the Pentagon for not investigating the Muslim organization that certified Yee as an appropriate military chaplain candidate.
Schumer said the American Muslim Armed Forces and Veteran Affairs Council is a subgroup of the American Muslim Foundation, which has been investigated by Customs agents for possible financial ties to terrorism. The groups have denied any terrorist ties.
Schumer said he requested a Defense Department investigation of the group in March, but the Pentagon had not started one.
"I fully support the teaching and worship of Islam in the military, but I think it's common sense to ensure the groups in charge of vetting people don't have links to terrorism," Schumer said.
Fox News' Bret Baier, Ian McCaleb and the Associated Press contributed to this report.