MOSCOW, August 5 (RIA Novosti) - Mahmoud Ahmadinejad was sworn in for his second term as Iran's president in a ceremony in the country's parliament on Wednesday.

Iran's supreme leader, Ayatollah Ali Khamenei, officially confirmed on Monday that Ahmadinejad, 52, was the winner of the country's disputed June 12 elections.

Although runner-up Mir Hossein Mousavi claimed the reelection of the hard-line president was marred by numerous irregularities, Iran's constitutional watchdog, the Guardian Council, confirmed the result after a partial recount.

Ahmadinejad's victory triggered mass protests by Mousavi's supporters. According to media reports, at least 30 people were killed and about 1,000 arrested in post-election violence, Iran's most severe unrest since the 1979 Islamic Revolution.

The Iranian authorities have agreed to release around 140 prisoners detained in the riots, but according to the media, some 200 people, including 50 opposition activists, remain in jail and will face trial.