BOGOTA, Colombia (AP) -- Colombian troops have captured a top leftist rebel commander suspected of masterminding the 1999 kidnapping of an entire congregation from a Roman Catholic church, the army said Sunday.

Ramiro Velez, a regional leader of the National Liberation Army, or ELN, the smaller of Colombia's two rebel groups, was arrested Saturday during an operation in Chachaui, 300 miles southwest of Bogota, said Gen. Reinaldo Castellanos.

"He directed all the terrorist activity in the southwest of the country. He is a very important commander, a member of the ELN's national directorate," Castellanos told reporters.

Velez, known by the alias "El Viejo" ("The Old Man"), is accused of rebellion, kidnapping and ordering attacks on villages and the country's energy infrastructure.

He is blamed for the May 1999 gunpoint abductions of 180 Roman Catholic worshippers from the La Maria church in the southwestern city of Cali, the army said in a statement.

The rebels later freed all the hostages but only after collecting hefty ransoms from their families. The ELN funds itself mainly through kidnappings.

Velez also has been implicated in the abduction of 81 people from roadside restaurants outside Cali a year later. Three hostages died of illness during their captivity and 78 others nearly starved before the army rescued them.

The Cuban-inspired ELN and the larger Revolutionary Armed Forces of Colombia, or FARC, have been battling for Socialist-style revolution in Colombia for 40 years in a conflict that claims more than 3,000 lives -- mainly civilian -- every year.

In the past two years, however, a military offensive ordered by President Alvaro Uribe is believed to have dealt a severe blow to the ELN, and army officials say the group is suffering from mass desertions.

Copyright 2004 The Associated Press.