Protesters in Baghdad and southern cities defied a government curfew on Thursday as security forces used live ammunition and the government closed two border crossings with Iran.
Curfew regulations were in place in three southern Iraqi regions, Al-Amarah, Naseriyeh and Hellah since Wednesday. The government also cut internet connection to prevent protesters organizing.
Iraq has nine border crossings with Iran but the two locations where the border is shut down are close to holy Shiite sites where Iranian pilgrims often visit.
Iraqi security officials also said unknown attackers have shot and killed an activist in the southern city of Basra who was active in the ongoing protests. Hussein Adel Madani and his wife were killed by masked gunmen in their house on Thursday.
The streets of Baghdad were littered with tear gas canisters and empty bullet casings. Smoke from burned tires rose above the streets as protesters tried to prevent security forces from advancing. The forces spread barbed wires and armored vehicles to block their path.
Meanwhile, two rockets have targeted Baghdad's high security Green Zone. One rocket landed somewhere near the Embassy of Turkey and another one hit a nearby bridge.
Ongoing protests which escalated on Tuesday centered around mainly social demands for wide-ranging reforms to fight rampant corruption, unemployment and improvement of basic services particularly electricity, without any clear indication yet of an outside influence or motivator.
Most protesters are young and do not appear to belong to political parties.
The protests seem to have suddenly started a few days after the the removal of the popular commander of Counter-Terrorism Forces from his post.
Reports say Iraq has cut-off social media access in most parts of the country except in the Iraqi Kurdistan.