Alexander Solzhenitsyn, the Nobel prize winner for literature,died at age 89, the news agency Interfax reported early Monday.

The agency quoted literary circles in the Russian capital, where he was living since 1994 after the fall of the Soviet Union.

The world famous writer and historian had not been seen in public for months, and had reportedly been seriously ill for months. He died from the aftermath of a stroke, according to unconfirmed information.

Solzhenitsyn's main work was the massive Gulag Archipelago, first published in the West in 1973, which described the years of Stalinist terror using thousands of details and individual cases.

The three-volume work, published between 1973 and 1976 in the West, is considered the most important work of the Soviet dissident and Nobel Prize winner.
The literary attack on the Soviet system prompted Soviet authorities to arrest, then expel, the writer in 1974.
Solzhenitsyn, a mathematician by training, dedicated the book to all those who did not have enough life left to tell their stories.
Solzhenitsyn knew the subject first hand. From 1945 on, he spent time in and out of the camps for alleged anti-Soviet propaganda. He called his works an attempt to artistically overcome his experiences in the camp system.
In thousands of examples, he describes the minutiae of the Soviet terror: arrest, interrogation, torture, forced labour, survival or death by the millions in Stalin's labour camps.

Solzhenitsyn began his work on the Gulag Archipelago in 1958 under conspiratorial conditions. In 1973, the Soviet secret police KGB discovered parts of the manuscript, which Solzhenitsyn then hurriedly had smuggled into the West for publication.

Moscow reacted with sharp protests and expelled the writer in 1974, but Gulag circulated in the Soviet Union in secret form under the samizdat - or underground - publication system.

The books were only published and became officially available in the Soviet Union in 1989, during the time of Perestroika which led to the dissolution of the Soviet empire.

The works are not only historical documentation, but also are acknowledged as Solzhenitsyn's greatest literary achievement.

He uses bitter irony to describe the torturers and executioners, and deep mourning for the victims. Alongside the gruesome experiences and humiliation of the prisoners, he writes of their moral courage.

"It gradually became clear to me, that the line between good and evil lies not between states, not between classes and not between parties, but rather cuts across every human heart," Solzhenitsyn wrote in one section of Gulag called "Soul and Barbed Wire."

He received the Nobel Prize in 1970 after the 1968 publication in the West of First Circle, based on his experiences in a work camp that was a special scientific research facility.

In 2007, the one-time exile received the highest Russian government award for his work in the humanities - the Russian State Prize.

In announcing the prize last year, Yury Osipov, president of the Russian Academy of Sciences, called Solzhenitsyn "the author of works without which the history of the 20th century is unthinkable."

One of Solzhenitsyn's first, most famous books, a slender volume called One Day in the Life of Ivan Denisovich, appeared in 1963 in English at the height of the Cold War.

It was the story of a former prisoner of war caught by the Germans during World War II, then returned home only to face charges of being a spy - a fate that awaited many POWs returning home to the Soviet Union.

Solzhenitsyn did not attend the announcement of the state prize in Moscow's Kremlin in 2007, but his wife Natalya said the writer hoped his study of Russia's history would help the country in the future.

The prize, she said, "gives a certain hope, and Alexander Isayevich (Solzhenitsyn) would be glad if that hope came to life, a hope our country will learn the lesson of its self-destruction in the 20th century and not repeat it."

The State Prize's origins date back to Soviet times, but Solzhenitsyn was just the second person to receive the prize for work in the humanities.

Russian Orthodox Patriarch Alexiy II received the first such prize in 2006.