MANILA, Philippines -- Exactly a week since the Maguindanao massacre, press organizations and militant groups will hold a "march against impunity" to the Don Chino Roces Monument in Manila on Monday, to call for an end to political violence, and demand swift justice for the victims in the worst election-related atrocity in the country.

In a statement, the left-wing Bagong Alyansang Makabayan (Bayan) called the mass killings the "Ampatuan Massacre," an obvious reference to the town where at least 64 people were killed, and to the prime suspect, Mayor Andal Ampatuan, Jr., who is now detained on murder charges at the National Bureau of Investigation (NBI).

Bayan said the protest action would be the "first multi-sectoral march to Mendiola bridge" since the mass killings that sent shock waves all over the world for its brutality and brazenness.

Authorities were able to recover 64 bullet-riddled bodies, some buried in a grave 20 feet deep. The victims are close relatives and supporters of local politician Esmael Mangudadatu, journalists, lawyers, and innocent passers-by who were unfortunate to have been at the tail end of the convoy that was heading to the election office in Shariff Aguak where the convoy was supposed to file Mangudadatu's candidacy papers for governor of Maguindanao.

Mayor Ampatuan is said to be being groomed by his father, incumbent Maguindanao Gov. Andal Ampatuan, Sr., to take over his post in 2010. The older Ampatuan ran for governor unopposed in the 2007 local elections.

The "March Against Impunity! March for Justice!" will be participated in by the National Union of Peoples Lawyers (NUPL), the National Press Club (NPC), the National Union of Journalists of the Philippines (NUJP), Karapatan, Gabriela, Solidarity Philippines, Bagong Alyansang Makabayan (BAYAN), Gabriela, Pagbabago and the College Editors Guild of the Philippines.

"This is just the start of many multi-sectoral protests until the killings stop and justice for the victims is achieved. This is not only an issue of journalists, or an issue of election violence. This is a people’s issue, a human rights issue that everyone should feel strongly about," said Bayan secretary general Renato Reyes, Jr. in a statement.

Bayan has also called on its chapters nationwide and abroad to hold similar protest actions to press the Arroyo administration to deliver "swift justice" to the victims.

Also calling the killings the "Ampatuan Massacre," Amnesty International will spearhead a protest action of some 300 youth activists from Mindanao and Visayas at 6 pm on Monday, at the Magsaysay Park in Cagayan de Oro City.

"The protest rally is in solidarity with the victims of impunity and 'guns, goons, and golds' during elections," said Mei Orias of Amnesty International in an advisory.

Reyes added that instead of eyeing a congressional seat in the 2010 elections, President Macapagal-Arroyo should resign over the killings.

The Bayan leader said that her government should be held accountable for the climate of impunity and the denial of justice for the victims of human rights violations such as extrajudicial killings since she was swept to power in 2001.

"No doubt, the failure of government to curb these abuses and bring the perpetrators to justice has emboldened killers all over the country. Instead of running for Congress, Arroyo should step down over the killings," Reyes said.

Reacting to reports that Ms Arroyo would file her candidacy on Monday, Bayan said that it would only "fuel more outrage against the regime."

"That would be grossly insensitive, seeking to prolong her stay in power, just one week after the massacre in Maguindanao. She appears to be more concerned about seeking office and gaining immunity rather than addressing the problem of impunity," Reyes said.