George Papadopoulos, 80, a former Greek army colonel who rose from relative obscurity to become the feared ringleader of Greece's 1967 to 1974 military dictatorship, died of cancer June 27 in a hospital here. He also had a degenerative muscle disorder.

The military junta, under his command, tortured and jailed thousands of Greeks. At the time of his death, he was serving a life prison sentence.

In 1975, he had been sentenced to die by firing squad for treason, but the sentence was reduced. A decision by the government to free him on humanitarian grounds in 1990 was reversed after a public outcry and firestorm of protest by opposition parties.

Col. Papadopoulos was deposed as the self-appointed Greek president in 1973 by his armed forces. The junta limped along for several months but eventually collapsed in July 1974.

Col. Papadopoulos was jailed in a special wing of Athens Korydallos maximum-security prison but spent most of the last three years in a hospital.

Guards at Korydallos have said he never regretted his role in the coup, "insisting to the last moment that he saved Greece from communism."

Col. Papadopoulos, a highly decorated officer during 27 years of military service, also lost his civil rights for life.

The army colonel, who once said U.S. President Richard M. Nixon and two-thirds of the American Congress were communists, attempted a political comeback from behind bars in 1984. From his jail cell, he headed the National Political Union party, which won a seat in European elections.

Col. Papadopoulos defended his record in a recording smuggled from prison in 1984. He justified the expertly planned and swiftly executed coup, saying that at the time, the unsettled political situation could have led to a communist takeover.

A report by the European Commission on Human Rights later asserted that no communist threat existed.

The report also concluded that the regime tortured prisoners as a matter of policy and denied fundamental human rights to citizens. Thousands of Greeks were jailed or ordered into internal exile on remote islands or driven into foreign exile by the junta.

A counter-coup by former King Constantine failed in December 1967. Constantine fled into exile, and Col. Papadopoulos appointed himself prime minister, imposing restrictions on press freedom and personal liberty.

In 1968, he survived an attempt on his life when a bomb exploded near his car. He formally abolished the monarchy in June 1973, and a month later named himself president of a new republic for an eight-year term.

His downfall came when he called in troops in November 1973 to crush a student uprising at the Athens Polytechnic school. At least 50 people were killed and more than 1,000 injured.

Maj. Gen. Dimitrios Ioannides, chief of the military police, seized on the incident to oust Col. Papadopoulos. Ioannides took power, and the army put Col. Papadopoulos under house arrest.

Ioannides's days were numbered from the outset, and his role in an attempted coup to topple the Greek Cypriot president of Cyprus spelled the end of a seven-year dictatorship in Greece.

Col. Papadopoulos was born into a poor family in the northern Peloponnesian village of Eleochorion. In 1940, he graduated first in his class at the Greek Military Academy and was commissioned a second lieutenant.

He fought in the front lines after Italy attacked Greece in 1940, during World War II. During the German occupation, he fought in the resistance, but he always considered communism a greater menace than the Nazis.

In 1959, he was posted to the Central Intelligence Service, becoming chief of national security and counterintelligence, and from 1964 until 1967, he commanded artillery units.

Survivors include his wife, Despina.