MANILA - The Philippines has become the most dangerous place in the world for journalists, according to an international press watchdog, after an election-linked massacre of at least 57 people this week.

The Belgium-based International Federation of Journalists said that by its count at least 12 journalists and "around eight media staff" were among the victims of the mass killing, blamed on a local politician and his bodyguards.

"Under the current government the Philippines has become the most dangerous place in the world for media workers," the group said in a statement, urging President Gloria Arroyo's government to give the press more protection.

"At least 74 journalists have been killed during its eight-year tenure, yet the government has not acted to end the culture of impunity. At last count, only four convictions had been secured," it said.

The group said it would send an investigative mission to the southern Philippines region of Mindanao, where the killings happened on Monday.

"The Arroyo administration must make a clear and unequivocal commitment to an immediate, independent and effective inquiry into this atrocity," said the group's general secretary Aidan White.

"With elections due in six months' time the authorities must act now to guarantee the safety of journalists throughout the country."

Arroyo on Wednesday vowed to hunt down the perpetrators of the massacre.

Police have identified the top suspect as Andal Ampatuan Jnr, a member of Arroyo's ruling coalition and the son of a powerful regional politician who has helped secure votes for the president in previous elections.

The victims were abducted as they were travelling in a six-vehicle convoy to nominate a rival of the Ampatuan clan as the opposition candidate for provincial governor in elections next year.