Former president-turned-dictator Juan Maria Bordaberry and his foreign minister were in police custody Friday, arrested in connection with a series of "dirty war" murders.

Bordaberry and former foreign minister Juan Blanco were taken to the main police investigations unit awaiting judge's orders, police spokesman Celso Sosa said. Their arrests were ordered by Judge Roberto Timbal, who is probing the abductions and killings of two former lawmakers and two leftist rebels in May 1976.

Zelmar Michelini and Hector Gutierrez, two prominent lawmakers who tried to flee Uruguay's dictatorship, were seized from their homes in exile in Buenos Aires, Argentina, and their bullet-riddled bodies were found days later, along with those of the suspected guerrillas William Whitelaw and Rosario Barredo.

Human rights groups have long contended that the killings were the result of secret cooperation by the two countries' military dictatorships. Under the so-called Operation Condor, authoritarian governments that dominated South America during much of the second half of the 20th century worked together to crack down on rebels and political dissidents, resulting in the death and disappearance of unknown thousands.

Elected democratically in 1971, Bordaberry dissolved Congress and banned political parties the following year at the behest of military leaders who seized power outright in 1973. The military eventually ousted him in 1976, and Uruguay remained under the control of a right-wing dictatorship until 1985.

Tabare Vazquez, Uruguay's first elected leftist president, who has made prosecuting human rights violations under the dictatorship a priority, told reporters that "the justice system has spoken" but otherwise did not comment.

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