Article published on the 2009-11-23 Latest update 2009-11-24 10:04 TU
The victims were found five kilometers from where they had been abducted, from Maguindanao province in the southern region of Mindanao, at around 9.30am on Monday morning.
They had been part of a convoy of local journalists, lawyers and supporters travelling to file the candidacy of local politician Ismael Mangudadatu for the governorship of Maguindanao in next year's national elections.
According to military spokesmen, around 100 gunmen attacked the party's vehicles as they stopped at a roadside checkpoint.
At least 15 members of the convoy are still missing. The military says that clearing operations are underway to find them.
Ismael Mangudadatu, who was not in the convoy, has accused his political rivals of organising the massacre. He said that his wife and relatives were among the dead.
Mangudadatu managed to speak to his wife before she was killed and she claimed that a rival political family was behind the attack, correspondent Girlie Linao told RFI.
"Authorities are saying that [this family], the Ampatuans, are the suspects in the incident, but of course they still have to investigate it."
There is a "longstanding feud" between the Mangudadatu family and the Ampatuan family, Lindao explained.
Zaldy Uy Ampatuan currently holds the post of Governor of Maguindanao for which Mangudadatu hopes to compete in the next elections.
Mangudadatu had received death threats as he prepared to launch his candidacy, Lindao said. He decided to send his wife and female relatives to file his nomation papers, believing that they would be safe from attack because they were women.
Clan rivalries have led to violence during previous Philippine election campaigns, especially as political warlords form their own private militia.
Yet this attack is "unequalled in recent history," said Jesus Dureza, adviser on the volatile Mindanao region to Philippine President Gloria Arroyo.
"I strongly recommend that a state of emergency be imposed in the area and everyone be disarmed," he urged. "Anything less will not work."
"Justice will be served and the perpetrators punished, whoever they are," declared another presidential adviser, Gabriel Claudio.
The Philippines will hold local and national elections in May 2010.