Wednesday in the Philippines security forces found 11 more bodies at the site of a massacre in the south of the country. The death toll has increased up to 57 dead, officials said.
Not all have been identified, but 22 of them were believed to be journalists, making Monday's attack the deadliest ever on the media anywhere in the world. Thirty-three of the victims were men and 24 were women, police said.
The government has clamped emergency rule on the province of Maguindanao, where the killings took place, and in adjoining Sultan Kudarat province and Cotabato City. Truckloads of troops were brought to the area on Wednesday and armoured cars were parked along highways.
"The perpetrators will not escape justice," President Gloria Macapagal Arroyo told reporters. "The law will hunt them until they are caught," Reuters reports.
It was also reported, the victims were in a convoy of vehicles Monday heading to register a candidate to challenge Ampatuan in next year's election for governor.
Among the dead are the wife and sisters of the challenger, Ismael Mangudadatu.
Amina Rasul is the director of the Philippines Council for Islam and Democracy. She says despite the police investigation it will be difficult for authorities to enter Ampatuan territory, let alone arrest a member of the family.
"Most of the electeds [elected politicians] are Ampatuans, the police are their people, it's very difficult to get in without having more violence if they do not cooperate," said Rasul, Voice of America reports.
Meanwhile, Human Rights Watch in New York urged the government to start a fully independent investigation led by the national bureau of investigation, given allegations of involvement by members of the security forces and local militias.
"Far too many people have been gunned down in the Philippines while President Arroyo has sat on her hands," said Elaine Pearson, deputy Asia director at Human Rights Watch. "The possible involvement of state forces in the Maguindanao massacre means that security personnel shouldn't be allowed to interfere in an independent investigation."
But human rights officials voiced fears that the Philippine government would pull its punches in any investigation because the Ampatuans have helped deliver votes for Arroyo in past elections.
"I have run out of words to describe this. It's ignominious, bestial," Leila de Lima, the chair of the independent commission on human rights, told the Associated Press. She said there was "strong circumstantial evidence" implicating the Ampatuans, guardian.co.uk reports.