POSTED AT 7:12 PM EST Friday, Dec. 12, 2003

Calling themselves "conscientious objectors," the collection of farmers, teachers and human-rights advocates said they will not co-operate with authorities conducting investigations of such suspects and, if arrested, will refuse legal counsel.

"We refuse to contribute to false justice," the ad-hoc group said in a statement this week.

Further upsetting the opponents of the mass-arrests, Colombia's Senate approved an anti-terrorism bill Thursday giving the military sweeping powers to search homes, detain suspects without warrants and wiretap phones.

On Friday, the UN Office of the High Commissioner for Human Rights expressed its displeasure with the new anti-terrorism law, saying it could pave the way for arbitrary arrests.

In a statement, the office said it believes Colombia already has sufficient constitutional and legal powers at its disposal to fight terrorism.

Human-rights groups have denounced the mass-arrests as arbitrary, saying suspects picked up in such sweeps are usually released for lack of evidence.

But President Alvaro Uribe, who has cracked down on guerrillas waging war for the last four decades, has defended the practice.

"Some national and international observers don't like it but really it's a way to isolate terrorists," Mr. Uribe said Wednesday.

Critics argue it is just a way to punish opponents of the government.

"It's worrisome that the jails are filled with men and women who think differently from the government," said Gloria Cuartas, a former mayor of Apartado, where activists signed on to this week's boycott of the justice system.

Seven years ago, community leaders in northwestwen Colombia — where fighting between the military, guerrillas and right-wing paramilitary squads have plagued the region for decades — declared their towns "peace communities," in an attempt to bar the armed groups from entering.

Nonetheless, more than 120 residents have been killed by the warring factions since then, said Wilson David, a village leader in San Jose de Apartado, near Apartado city.

These days, innocent residents are being thrown into jail, said David, who was temporarily detained by the army earlier this year.

Colombian Senator Carlos Gaviria also criticized the detentions.

"These communities have declared themselves neutral to the conflict, yet they are treated as if they were linked to the rebels," Mr. Gaviria said.

A union of legal workers is one of those supporting the activists' initiative.

"We feel the constitution is being uprooted and that there are serious human-rights abuses being committed by the attorney general's office in its work with the army and the police," said Luis Fernando Otalvaro, president of the ASONAL Judicial union.