The head of Georgia's rebel Abkhazia region Sergei Bagapsh, died on Sunday in a Moscow hospital after lung surgery, Abkhaz officials told Reuters.

Bagapsh, 62, in power since 2005, was re-elected as the head of the separatist region in December 2009, slightly over a year after Russian forces defeated Georgia in a five-day war and proclaimed the region's independence.

I spoke to him three days ago. The president was already up and about, but two days ago his condition worsened suddenly. He lost consciousness, his spokesman Christian Bzhania told Russian state television. After the operation doctors discovered that Bagapsh also ahd cancer, he added.

Moscow recognized South Ossetia and Abkhazia's independence from Tbilisi after a five-day war in August 2008.

A black ribbon was tied to the Abkhaz flag flying over the province's embassy in Moscow on Sunday, Reuters reported.

Bagapsh was a loyal supporter of friendship and alliance with Russia, and he determinedly worked to deepen close bilateral ties between our countries, Medvedev said in a statement on the Kremlin's website.

Alexander Ankvab, 58, Bagapsh's deputy, will take over as acting president, and new elections will be held within three months according to the region's constitution.

We are profoundly shocked by Sergei Bagapsh's death, Ankvab told Interfax news agency.This is a great loss for the Abkhaz people, he said.