BAGHDAD: Thousands of supporters of Iraqi cleric Moqtada Sadr defied a government ban Friday to stage sit-ins at the main gates of Baghdad’s Green Zone aimed at pushing for reforms.

Most of the demonstrators were wearing black and many of them carried Iraqi flags as they muscled past tight security to begin what they said was an open-ended protest.

“The sit-ins have started in front of the Green Zone gates as a message to the corrupt people who live there,” Ibrahim Al-Jaberi, a local official from Sadr’s movement, told AFP.

The Najaf-based Sadr has called his supporters to remain in front of the fortified “Green Zone” — home to the country’s main institutions and embassies — until his demands are met.

The young Shiite cleric has demanded Prime Minister Haider Al-Abadi reshuffle the cabinet to bring in technocrats and threatened a no-confidence vote if he failed to do so soon.

“The sit-in is open-ended,” said Jaberi, as Sadr followers started laying out sheets and blankets on the street and under trees in front of the Green Zone gates.

Their move was in defiance of a cabinet decision denying the rally the necessary permits and a warning from the Interior Ministry not to provoke the security services.

Sadr had issued a statement on Thursday saying his movement would ignore the ban but also calling on his supporters to refrain from violence in dealing with the security forces.

Sadr heads a militia called Saraya Al-Salam (Peace Brigades) that had caused intense concern when it deployed armed men during a previous protest in Baghdad.

Amid fears the stand-off could escalate, Iraqi security forces locked down Baghdad, the Arab world’s second most populous capital with an estimated eight million residents.

“All entrances to Baghdad have been blocked and some main streets and bridges are also closed, especially those leading to the Green Zone,” a police colonel said.

A group of Sadrist demonstrators clipped the barbed wire on one of the bridges over the Tigris river to reach an entrance to the sprawling Green Zone but no violence ensued.

“We’ll stay days, weeks or months if needed, until the government implements reform and sacks all the corrupt politicians,” said one demonstrator, Muntadher Kadhem, a 25-year-old history student.

Moqtada Sadr, the scion of an influential clerical family, rose to prominence when he launched a Shiite rebellion against US troops following their 2003 invasion of Iraq.

He had lost some of his political influence in recent years but has brought himself back into relevance with a series of rallies against corruption.