MANILA, Philippines?(UPDATE) Protesters calling for justice for victims in the Mindanao massacre booed and threw garbage at Press Secretary Cerge Remonde, who tried to talk to protesters.

Shouting "tuta (lapdog)? and "berdugo (executioner),? protesters insisted Remonde should not be given the chance to address the public.

Remonde, who walked for a few meters from Malacanang to the rally site in Mendiola, tried to pacify the crowd by blowing kisses but crumpled paper and bottles flew his way.

The press secretary was immediately whisked away by the police.

Some 5,000 protesters, led by journalists, trooped to Mendiola Monday in what they called March Against Impunity, March for Justice.

They criticized the government for its slow action on the massacre which claimed the lives of at least 64 people, including more that 30 members of the media.

Speaking to reporters, Remonde said, "We are one with them in condemning this killing and upholding press freedom and we assure everyone that justice will be served."

"Against all advice, I went with them. I sincerely feel as strong as anyone...But I guess the rules of civility are no longer present among some people," Remonde said.

But he thanked the leaders of the mass action, including militant party-list Representatives Satur Ocampo and Liza Maza, for acknowledging his efforts.

The Confederation of Asean Journalists (CAJ) urged the use of the full force of the Philippine judicial system and the national security forces to prosecute those responsible in the carnage.

Norila Daud, president of CAJ, said "truly the incident in Maguindanao has no parallel, has dwarfed the other incidents of violence against journalists in particular and the media in general in any part of the world."

"Words are not enough to describe the depth of anguish that we at the CAJ, as well as journalists everywhere, now feel over this mass killing in a single day, of our fellow media practitioners," Daud said.

Joining the march are members of 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.

The protest action ended after two hours with the protesters singing "Bayan ko" and leaders of various media organizations tying black ribbons on the barbed wire along the historic bridge.