Twenty-one politicians and journalists who were abducted in the southern Philippines have been found dead.
Jesus Dureza, adviser to President Gloria Arroyo in the volatile Mindanao region, said it was “a gruesome massacre of civilians unequalled in recent history”.
He recommended that a state of emergency be imposed in the area.
In a statement, Mrs Arroyo condemned the violence and said no effort would be spared to find those responsible.
“Civilised society has no place for this kind of violence,” she said.