MANILA, Philippines -- The protest staged by leftists to commemorate the 21st anniversary on Tuesday of the Mendiola massacre, in which 13 farmers died when security forces fired on marchers demanding agrarian reform, ended peacefully with the activists dispersing around 4:20 p.m.

However, the rally they held at a university near historic Mendiola Bridge, which they were prevented from reaching by authorities, was briefly disrupted by the arrest of two suspected military intelligence operatives and an alleged personnel of the Commission on Human Rights, activists and police said.

Renato Reyes, secretary general of the Bagong Alyansang Makabayan (Bayan, New Patriotic Alliance) said one of the arrested agents had been taking videos of the rallyists.

"He was not a member of the media so why should he take videos? His presence is very suspicious," said Reyes.

Carl Ala, spokesman of Kilusang Magbubukid ng Pilipinas (KMP, Peasant Movement of the Philippines) said another agent had been arrested.

On the other hand, Chief Superintendent Roberto Rosales, director of the Manila Police District, said the alleged CHR workers had been arrested with a 9millimeter firearm.

"He could face charges of illegal possession of firearms," Rosales said.

The marchers, composed mostly of militant lawmakers and groups, were stopped from getting to Mendiola Bridge, renamed Chino Roces, and instead gathered near the University of the East where, through the intervention of Manila Mayor Alfredo Lim, they were allowed by police to stay.

Lim’s action earned him the “trust and respect” of the rallyists, said Bayan’s Reyes.

Rosales said Lim's presence eased the tension.

"There was assurance from the ranks [of protesters] it would be a peaceful rally,' said
Rosales.

Earlier in the day, the marchers, who had no rally permit, were also stopped then eventually allowed to cross Welcome Rotonda, the boundary between Manila and Quezon City.

Police officials expressed confidence that the rallies would be peaceful, although earlier government officials claimed the existence of a destabilization plot supposed to be launched on the anniversary of the Mendiola massacre.

Police Director Geary Barias, chief of the National Capital Region Police Office, said that some 2000 policemen were deployed in the area.

The protesters wanted to light candles at Mendiola for the 13 farmers who were shot dead during a clampdown on farmers' demonstrations in 1987. A year later, then-president Corazon Aquino signed the Comprehensive Agrarian Reform Law that redistributed land to tenant farmers.

Until then, nearly all farmland was owned by a handful of powerful families, and half of the country's estimated 10 million farmers were landless or squatters.

Despite a massive restructuring of land tenure in the country, militant farmers say not all land has been distributed and that genuine land reform has yet to take place.

Military and police officials warned last week that communist rebels and certain soldiers were plotting to oust President Gloria Macapagal Arroyo on the anniversary of the 2001 military-backed revolt that toppled her predecessor, Joseph Estrada, and installed her as president.

Arroyo left for the Swiss resort of Davos early Tuesday to attend the World Economic Forum, and her spokesman Ignacio Bunye said the president was confident security forces would fend off any threats to her government.

Arroyo has survived four coup attempts and three opposition impeachment bids over allegations of vote-rigging, corruption and human rights abuses during her seven tumultuous years in power.