The Philippine military says an accidental grenade blast killed a communist rebel and wounded 11 civilians, including seven children.
Col. Leopoldo Galon said rebels were conducting lectures in a village in southern Bukidnon province's Kibawe township when a guerrilla accidentally dropped a grenade.
It was not immediately clear if the rebel who died was the one who dropped the grenade.
The seven children hurt in Monday's blast are aged 9 to 16.
The rebels have been fighting for a Marxist state since 1969 and are listed by Washington as terrorists.