MANILA, Philippines?(UPDATE 3) An ex-colonel in the Philippine Marines who is on trial over a failed coup against then president Gloria Macapagal-Arroyo was released from detention on Wednesday after more than four years in military custody.

Ariel Querubin walked out of a detention facility at Camp Aguinaldo and was placed under the watch of a top-ranking soldier, Army spokesman Lieutenant Colonel Marcelo Burgos said.

"He was granted provisional liberty while his case remains on trial. He is now free to roam around, although he has to appear before the court if asked to do so," Burgos told Agence France-Presse.

The case was reviewed by military chiefs and it was determined there was no risk of flight, Burgos said.

Querubin will be placed under the custodial care of his senior officer General Reynaldo Ordoñez, said Mabanta, Armed Forces of the Philippines spokesman Brigadier General Jose Mabanta said.

AFP Chief of Staff Ricardo David Jr. approved Querubin?s release Tuesday night by virtue of the Articles of War 70, Brigadier General Jose Mabanta said Wednesday.

Mabanta stressed that Querubin did not ask for the provisional liberty.

"He did not ask for it,? Mabanta told INQUIRER.net. ?It was so decided by the Chief of Staff after consultation with the Judge Advocate General.?

Querubin, 53, was jubilant after winning his freedom.

"There is light at the end of the tunnel," he told reporters.

"I will take a vacation first with my family and after that [I will have] to think about going to work again."

In a telephone interview aired over a television morning show, Querubin said that he had a "cordial meeting" with the new chief of staff last week.

"Ako'y nagpapasalamat sa AFP leadership sa pagheed sa panawagan ng bagong admin [I am thankful to the AFP leadership for heeding the call of the new administration]," Querubin said, adding that it was through the chief of staff's initiative that his release was approved.

Burgos said the case would continue to be heard in military court.

But he gave no timeframe for the proceedings and similar cases against alleged coup plotters have in the past dragged on for years before light sentences were eventually handed down or amnesties granted.

A Medal of Valor awardee, Querubin was one of two senior military officers charged and detained for a standoff at the Marine headquarters in 2006, which then-president Arroyo said was part of a larger plot to topple her government.

The other officer, ex-Scout Ranger Brigadier General Danilo Lim, was freed in June ? shortly after Benigno Aquino III became president ? under the same arrangement.

Both men tried their hands in politics in the May elections, but lost their campaigns for Senate seats.

The Philippines has a history of coup attempts, mostly carried out by officers demanding reforms amid a culture of political corruption.

The late president Corazon Aquino quashed at least seven coup attempts during her six-year term that ended in 1992.

A military-backed popular uprising toppled the graft-tainted government of Joseph Estrada in 2001, and he was replaced by Arroyo.

Arroyo withstood three attempts during her more than nine years in power.

Arroyo was succeeded on June 30 by Benigno Aquino, Corazon's son, who shortly after assuming power vowed widespread reforms within the military, including a long-delayed modernization program.