They are the first cases, of 21 reviewed thus far, to be decided. There is no appeal process.
Navy Secretary Gordon England, who is overseeing the reviews but has no say in the outcome of individual cases, told reporters at the Pentagon on Friday that the process, which began July 30, has proven more time consuming than expected, mainly because of translation requirements.
England said he expected that all of the nearly 600 terror suspects held at Guantanamo Bay will have their cases heard by the end of the year. Any who are determined to be improperly classified as "enemy combatants" would be released to their home country, officials have said.
The names and nationalities of the four suspects whose cases have been decided have not been made public. England said the countries involved would be notified Friday by the State Department.
Human rights lawyers criticize the hearings as a sham, pointing out that the detainees are not allowed lawyers and saying the officers hearing cases can't be considered impartial. The Pentagon calls the officers "neutral" because they have had no involvement with the suspects.
The military reviews were set up by the Pentagon in response to a June 28 Supreme Court decision that allows detainees to challenge their imprisonment in federal courts.
This is separate from a more elaborate military tribunal, which the Pentagon calls a military commission, which was established by President Bush in 2002 and is designed to conduct trials of non-American terrorist suspects at Guantanamo Bay. No such trials have been held yet, although the U.S. government has designated 15 people at Guantanamo Bay as eligible for trial.
England said the sole purpose of the reviews, known officially as Combatant Status Review Tribunals, is to determine whether a detainee is an "enemy combatant." The Pentagon defines an "enemy combatant" as "an individual who was part of or supporting Taliban or al Qaeda forces, or associated forces engaged in hostilities against the United States or its coalition partners" during the 2001 war in Afghanistan or elsewhere.
Most of the people held at Guantanamo Bay were picked up on the battlefields in Afghanistan and have been held for questioning aimed mainly at gathering intelligence that could prevent another terrorist attack against the United States. Human rights groups have challenged the Bush administration's position that the detainees can be held indefinitely without being charged.