BOGOTA, Colombia - A rebel group usually scorned for its tactics won praise Saturday after it freed 26 members of a scientific expedition that had been held captive in a mountainous war zone.
Armed rebels, clad in camouflage fatigues and masked by kerchiefs, released the university team in the grassy highlands of western Colombia shortly after midnight. The weary former captives grinned as they were handed over to human rights, church and justice officials.
The National Liberation Army, which has kidnapped hundreds of people - even airline passengers and worshippers at a church - earned high marks for the quick release.
''This is a gesture of good will, the liberation of this group of students and scientific commission, and that their captivity was not prolonged,'' said Maria Villegas, a government human rights official, who observed the handover.
The captives, including a retired American college professor, had been missing since Wednesday. Before they were released, they walked for four hours over rugged terrain, to a site near La Union village, 125 miles northwest of the capital Bogota. They were reported in good condition Saturday.
Rebel commander Nicolas Rodriguez said Friday that his forces had detained the scientists in Antioquia province to investigate their reason for being in the area. He told Colombia's Radionet Radio on Friday that was satisfied they were there for research, and he would free them.
The guerrilla group, known by its Spanish initials, ELN, intercepted the team from Colombia's National University as it drove along a road, the army said Friday. The captives were released at the same location, army Col. Juan Pablo Amaya said.
The group included one American, John Douglas Lynch, a native of Collins, Iowa.
Lynch recently retired from the University of Nebraska-Lincoln, where he was a biology professor for nearly 30 years.
He researched amphibians in Colombia for at least two decades and moved to Bogota when he retired. He is now a curator at the National Science Institute of Colombia.
The group also included six professors, five biologists, 10 students and several assistants, according to the National University.
Despite the rapid release of the hostages, there was little hope that it would provide a needed good-faith breakthrough to accelerate peace talks.
Peace talks last month in Geneva between the ELN and the Colombian government ended in stalemate.
The area where the team was working sees frequent clashes between leftist rebels and paramilitary groups backed by landowners. Colombia has one of the highest kidnapping rates in the world.