Philippine President Gloria Macapagal-Arroyo on Tuesday placed Maguindanao, the neighboring province of Sultan Kudarat and Cotabato city under the state of emergency, which gives police and military liberty to arrest and detain suspects.

"I order all units to pursue the perpetrators, to restore order and secure affected areas in Maguindanao," Arroyo told Tuesday's cabinet meeting, which was held in Manila instead of Boracay, the country's tourist island, because of the killing.

Residents gather at the scene of a massacre in the southern township of Ampatuan in Maguindanao, November 24, 2009.[Jef Maitem/Xinhua]

Press Secretary said Arroyo has assured an impartial investigation in "this unconscionable, barbaric and dastardly act" no matter who gets hurt.

National Police Chief Jesus Versoza flew into Maguindanao to personally direct the pursue and rescue operations.

"No one will be untouchable in this case," he said.

Meanwhile, more than 70 civilians gathered near one entrance of the Malacanang Presidential Palace at Tuesday noon time to rally for the massacre victims.

In between drizzles, they wore white head-bands, lit candles and held white flowers tied with banners saying "Justice for the victims of the Maguindanao Massacre".

Political violence is not uncommon in the Philippines, especially in Muslim Mindanao, a region plagued by decades of insurgency battles and flooded with loose arms.

But the indiscriminate killing of women, working journalists, and civilian supporters shocked the nation.

In a statement issued on Monday, the National Union of Journalists of the Philippines (NUJP) said they will hold accountable the civil and security officials in Mindanao for their failure to end "the culture of violence and warlordism that lays waste not only to those who engage in politics but to innocent victims as well."

The NUJP also called on fellow journalists "to band together and demand no less."

Presidential Adviser for Mindanao Jesus Dureza described the killing as a "gruesome massacre unequaled in recent history". He suggests "everyone be disarmed" in the emergency rule but most people doubt that the region's warlords would follow the order to lay down guns.

Political analysts now foresee a gloomy picture of election security as the massacre occurred just days after the process for the May 2010 elections kicked off. More than 100 people were killed in election-related violence in the last national elections in 2007.