The Patriarch of the Russian Orthodox Church, Alexei II, has died at the age of 79, ending a long church career in which he maintained close ties with the Kremlin and the Russian state.  

He died of a heart condition Friday morning at his residence outside of Moscow.  

Soon after Alexei's death was announced, Russia's all-news television channel, Vesti-24, switched to extensive coverage of his life, and Russian President Dmitri Medvedev expressed condolences from India, where he is currently on a working visit.

Mr. Medvedev said Alexei was not only a prominent religious and spiritual leader in Russia, but also a great citizen of the motherland.  He said the Patriarch was a person whose fate reflected all of the most difficult trials of the 20th century.  The Kremlin leader said Alexei was with his flock during times of persecution, and also during a period of religious revival.

Born in 1929 in Estonia as Alexei Ridiger, he entered a Russian Orthodox Monastery in Leningrad in 1947 and was elevated to church leader in June 1990, 18 months before the collapse of the former Soviet Union. Alexei was often seen at public events in the company of Kremlin rulers.  Vladimir Pribililovsky, an expert on Russian religious affairs at the Panorama think tank in Moscow, said the Patriarch maintained close ties to Russia's political establishment long before the Soviet collapse.

Pribilovsky said in Soviet times, Alexei supported the Communist Party line and continued the policy of complete Russian Orthodox loyalty to Soviet rule.

Pribilovsky said Alexei, who often supported the Kremlin's foreign policy, considered church subordination to the state a normal state of affairs.  

The Patriarch oversaw reconstruction of many churches throughout Russia and renewed ties with the Russian Orthodox Church abroad that had split from the main church following the 1917 Communist revolution.   He was also a staunch defender of Russian traditions, especially Orthodoxy, but opposed efforts by Catholics and Protestants to proselytize in Russia.  In addition, he blocked a visit to Russia by the head of the Roman Catholic Church and protested a 2001 visit to Ukraine by Pope John Paul II.

Alexei's full title was Patriarch of Moscow and all Rus, which was a state 1,000 years ago that covered what today is Ukraine, Belarus and Russia.  The seat of that realm was Kyiv, the capital of modern Ukraine, where the Orthodox Church has split into pro-Russian and pro-Ukrainian factions, each with millions of followers.   In an interview with VOA, Bishop Yevstratiy of the Ukrainian Orthodox Church repeated charges - also widespread in Russia, but denied by the Russian Orthodox Church - that Alexei served as a Soviet KGB agent.  Bishop Yevstratiy said Alexei used his position as church leader to continue Russian imperial influence in Ukraine and other former Soviet republics.

Bishop Yevstratiy said if a church is located in one nation, but its leadership is situated in another - especially if relations between those two countries happen not to be simple - then it becomes very difficult to overcome the temptation to use church structures of the neighboring state for political ends, which Yevstratiy said is what Alexei did in Ukraine.  

U.S. Ambassador John Beyerle issued a statement saying he was deeply saddened by the Patriarch's death, noting that the church leader will be remembered around the world for his leadership of the religious revival in Russia after the fall of Communism.

A Russian Orthodox spokesman said senior church officials will convene Friday to name an interim head until a new Patriarch is elected within six months.