Oca Lapida, media officer of Bayan Southern Tagalog said the protesters, numbering about 150, arrived in six passenger jeepneys and staged a protest at the EDSA gate of Camp Aguinaldo.
Lapida said the protest action was meant to signify their disgust over the governments all-out-war policy against the New Peoples Army, which he said has been victimizing innocent civilians in the countryside.
The protesters, wearing yellow raincoats with an image of President Arroyo depicting her as Nazi leader Adolf Hitler, called for the ouster of the Chief Executive.
"Malinaw ang posisyon ng Bayan, sobra nang pahirap ang dinaranas ng mga sibilyan at mga inosenteng mamamayan sa kanayunan dahil sa kagagawan ni Arroyo," Lapida said.
Despite the bad weather, the group said it would proceed with a torch parade to the Commission on Human Rights to protest the agencys alleged inability to address the worsening human rights situation in the country.
According to data from the militant group, a total of 137 political activists have been killed in Southern Tagalog since 2001, when Mrs. Arroyo first assumed the presidency.
The militant group has been blaming the military for the killings, but armed forces officials denied the accusations.
The Philippine National Police earlier put the blame on the Communist movement, saying its leadership ordered intensive operations against infiltrators among its ranks.