The government of the Philippines has declared a state of emergency in parts of the south after a massacre of at least 46 people, including 12 journalists. Press freedom groups have condemned the attack as the worst in history and express skepticism that those responsible will be brought to justice.

As more bodies were uncovered from the location of a massacre on the southern island of Mindanao Tuesday, President Gloria Macapagal Arroyo declared a state of emergency.

That allows the police and military to impose a curfew and conduct random searches as they hunt for those who carried out the attack.

Speaking on national television, Mrs. Arroyo said she is sending military leaders and the head of the national police to oversee the operation.

"No effort will be spared to bring justice to the victims and hold the perpetrators accountable to the full limit of the law," said Mrs. Arroyo.

The victims were seized Monday by gunmen as they drove in a convoy to register Ismael Mangudadatu as a candidate for governor of Maguindanao province. About 20 bodies were discovered later in the day, and the rest found on Tuesday.

The Philippine military suspects the politically powerful Ampatuan family is behind the attack and has deployed troops to search for the provincial governor, Andal Ampatuan and a militia loyal to him.

At least 12 journalists who were accompanying the group are among the dead.

Philippine elections often are violent, but Monday's attack was particularly shocking for its scope.

Rowena Paraan is director of the National Union of Journalists of the Philippines. She says election season has always been dangerous for Philippine journalists, but these killings are the worst in the country's history.

"It actually attacks two very fundamental foundations of democracy. One is election and the other is press freedom," she said.  "If you have problems with these two, and you're supposed to be in a democratic society, then I think there is a very big problem. And, it brings serious questions on whether there is indeed democracy in the Philippines or not."

Paraan says she is not very confident the government will prosecute those responsible for the killings, despite the Philippine president's declaration.

She says past investigations of political killings have produced few results.