TEHRAN, Iran (CNN)  -- With hundreds of protesters gathering and riot police out in force on the streets of Tehran, hardline President Mahmoud Ahmadinejad took the oath of office Wednesday, beginning a second term in a bitterly divided Iran. Mahmoud Ahmadinejad was sworn in Wednesday as Iran's president. He begins his second term. Ahmadinejad, 52, was formally sworn in before Iran's parliament, known as the Majlis, as security forces guarded the building and nearby streets in anticipation of protests. Witnesses reported a heavy police presence -- including members of the pro-government Basij militia -- and several choppers hovering overhead. Some reported protesters, many of them women, sitting in front of the parliament building's entrance.
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Mahmoud Ahmadinejad begins a second term as Iran's president
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The results of the June 12 election were widely disputed, sparking violent protests
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Since the vote, Iran has seen turmoil not witnessed since the 1979 Islamic revolution
"While we need to engage with @placeholder's government, today's ceremony does not change our position on Iran's elections," the Foreign Office said.