Calm has been restored in Baghdad, hours after security forces opened fire to stop protesters storming the Green Zone, reportedly injuring dozens. Tear gas and live bullets were fired to drive back the mainly Shia Muslim crowds, as they protested against corruption and security failures. Officials imposed a curfew in the Iraqi capital, which has now been lifted. It was the second time this month that protesters had managed to break into the city's government area. Shia Muslim cleric Moqtada Sadr condemned the use of force, and voiced support for the demonstrators' "peaceful [and] spontaneous revolt". At least 50 demonstrators are said to have been wounded. The protesters accuse the government of neglecting much-needed reforms, as it struggles with its campaign against the so-called Islamic State group (IS) and declining oil revenues. The Sunni jihadist group controls parts of western and northern Iraq and has been behind a wave of recent attacks that have left dozens killed. Some demonstrators managed to break into the prime minister's office and parliament. Baghdad's Green Zone houses the parliament, key government buildings and many foreign embassies. The authorities later said they had completely regained control of the area and the protesters had withdrawn. Prime Minister Haider al-Abadi, who came to power in 2014, has promised to stamp out corruption and ease sectarian tensions. He has been pressing for radical reforms and wants to form a government of technocrats, but has been blocked by lawmakers, the BBC's Jim Muir in Baghdad reports. Parliament is so deeply split that it cannot hold a meeting because no side can gather a quorum, our correspondent adds. Iraq's system of sharing government jobs has long been criticised for promoting unqualified candidates and encouraging corruption. The government is carefully balanced between party and religious loyalties but the country ranks 161st of 168 on corruption watchdog Transparency International's corruption perceptions index.