Human rights lawyers have said the arrest of the former leader of a German-Chilean religious cult could help them prove the cult aided the 1973-1990 dictatorship in the torture of political prisoners.
Chile's most-wanted man, 83-year-old German citizen Paul Schaefer, was arrested on Thursday in an elegant suburb of Buenos Aires in neighbouring Argentina after eight years on the run.
Schaefer was hospitalised yesterday after falling ill, Interpol in Argentina said, without giving any further details.
A Chilean judge convicted Schaefer in absentia last year for sexually abusing more than two dozen Chilean children lured to a free clinic and school at Villa Baviera, formerly Colonia Dignidad, a communal farm Schaefer founded in 1961 in southern Chile.
"This is going to be a huge step toward justice. Hopefully everything will be revealed," said Michael Muller, 48, who joined the cult with his mother when he was a child.
Last year, Muller broke the cult's decades-long silence when he said cult members were no longer loyal to Schaefer and publicly recognised there was abuse within the sect.
Schaefer is also wanted in Chile on accusations of responsibility in the disappearance of leftist Alvaro Vallejos, arrested in 1974 by ex-dictator Augusto Pinochet's secret police.
Vallejos was last sighted inside Colonia Dignidad, a 55-square mile property near the town of Parral, where Schaefer lived with some 300 German followers, who worshiped him as a god and had almost no contact with the outside world.
"The importance of the arrest is not only because of the Vallejos case," said Nelson Caucoto, a lawyer who represents the Vallejos' family. "Paul Schaefer has a long criminal history. ... Colonia Dignidad was a centre used by the military as part of its repressive actions."
A former secret police official previously testified that the secret police worked with the cult.
Cult members have denied they participated in torture but said they had friendly relations with the military, with whom they shared anti-communist philosophies.
Members also said they sided with the military for protection against Chileans, who wanted the cult shut down amid charges of tax evasion.
Chile, which has been run by a democratically elected centre-left government since Pinochet left power in 1990, has asked Argentina to deport Schaefer to avoid a lengthy extradition process.
In Germany, where Schaefer is also wanted on abuse charges, federal prosecutors said they also may seek extradition.
Cult members say they blindly followed Schaefer's dictates for decades. He preached an unnamed apocalyptic religion that extreme discipline would bring people closer to the supreme being and broke up families and prohibited contact between men and women.
Twenty-two Chilean and German members of the sect, mostly from the older generation, were convicted last year for their roles in covering up Schaefer's abuse or obstructing justice. They have appealed their sentences.