MOSCOW — Hundreds of demonstrators occupied the presidential headquarters of Abkhazia, a breakaway enclave of Georgia, on Wednesday, demanding the resignation of the region’s leader and the dismissal of the government in the latest tumult to grip a separatist area supported by Russia.

In a twist, though, the unrest does not stem from any disagreement over Russia’s role. Abkhazia is heavily reliant on Russia for economic aid and security, and the embattled president, Aleksandr Z. Ankvab, as well as his main critics, generally favor close ties with the Kremlin. Instead, it is an internal dispute that Russia is largely expected to mediate.

Mr. Ankvab, speaking on Abkhaz television, complained of an attempted coup. “This is definitely an armed attempt at a power grab,” he said.

Local television, however, showed several thousand demonstrators gathered peacefully in a palm-lined plaza outside the presidential building in Sukhumi, the capital, on the eastern shore of the Black Sea.