BAGHDAD — Anti-government protesters disbanded at least temporarily Sunday from the heavily fortified Green Zone they had stormed a day earlier, and the Islamic State group carried out its second major attack in Iraq in as many days – a pair of car bombs that killed more than 30 people.

The country’s political crisis had intensified Saturday when hundreds of supporters of Shiite cleric Muqtada al-Sadr tore down walls and poured into the zone that is home to the seat of the Iraqi government and most foreign embassies. Loudspeaker announcements Sunday evening urged protesters to leave peacefully. When the call came, hundreds calmly packed up and left, carrying flags and overnight bags away with them.

The Green Zone, surrounded by thick blast walls topped with razor wire, is off-limits to most Iraqis because of security procedures that require multiple checks and specific documentation to enter. It has long been the focus of al-Sadr’s criticism that the government is detached from the people.

Supporters of al-Sadr have been holding demonstrations and sit-ins for months to demand an overhaul of the political system put in place by the U.S. after the overthrow of Saddam Hussein in 2003. Last summer, demonstrations demanding better government services mobilized millions across Iraq and pressured Prime Minister Haider al-Abadi to submit his first package of reform proposals.

However, months of stalled progress followed, and in recent months al-Sadr’s supporters took over the protest movement.

Earlier Sunday, car bombs in the southern city of Samawah killed 31 people and wounded at least 52. On Saturday, an Islamic State-claimed bombing in a market filled with Shiite civilians in Baghdad killed at least 21 people and wounded at least 42.