The military said the incident occurred at the Army Training Ground (ATG) inside Camp Arturo Enrile in Barangay Malagutay at about 2 a.m. yesterday.
The identity of the slain soldier and the five wounded, who were rushed to Camp Navarro General Hospital (CGNH) inside the Southern Command headquarters, were not immediately made available.
But one of the victims, who was rushed to Zamboanga City Medical Center, was identified as a certain Reynaldo Basco. His companions who brought him to the civilian hospital refused to give details on the incident except that the grenade accidentally fell.
Lt. Col. Renoir Pascua, information chief of the Southern Command, said that initial investigation disclosed that the grenade explosion was an accident and that ongoing investigation has been conducted by the Task Force Zamboanga under Col. Jovencio Magalso.
"As of now, we cannot really determine the cause of the explosion except that the initial report showed that the blast was an accident," Pascua said.
Pascua said the victims were part of the army unit undergoing Special Forces training in Malagutay, the same camp that formerly housed the US Special Forces who trained the Filipino troops in anti-terror training during the Balikatan and Bayanihan exercizes in 2002 and last year.
Two of the US Special Forces also died in separate explosion incidents perpetrated by the Abu Sayyaf terrorists outside in the camp in Malagutay sometime in October 2002, when two other Filipino civilians were killed.