BAGHDAD (AP) — Iraqi security forces fired live ammunition and tear gas in renewed clashes with anti-government protesters in central Baghdad on Friday, killing three people, while Iraq’s top Shiite religious leader warned its government to heed calls for sweeping political reforms.

Separately, a bomb placed under a car exploded near a central square, killing two protesters and wounding 10 others, police and hospital officials said. They said the blast, which damaged several cars in the area, occurred between Tayaran and Tahrir squares, the latter being the epicenter of anti-government protests in the capital.

It was the first such incident in the capital since the demonstrations began in early October, although it was not immediately clear whether the explosion targeted the protesters.

Earlier, protesters repeatedly regrouped from under clouds of tear gas as they fought to tear down a concrete wall blocking access to Khilani Square. Security forces erected the barrier to keep the demonstrations from crossing a bridge that leads to the fortified Green Zone, the seat of government and many foreign embassies.

Tuk-tuk drivers ferried the injured back to makeshift medical tents stocked with saline used to douse demonstrators exposed to the tear gas. Many retched on the floor when they got there, saying the gas was the strongest they had ever experienced.

“We aren’t afraid of them, the authorities,” said Akeel, 21, who asked to be identified only by his first name.

Friday’s deaths brought to four the number of protesters killed in the past 24 hours around the square, the center of daily confrontations.

At least 320 people have been killed and thousands have been wounded since the unrest began on Oct. 1, when protesters took to the streets in the tens of thousands. They were outraged by what they said was widespread corruption, lack of job opportunities and poor basic services despite the country’s oil wealth.

Hours before the clashes erupted, Grand Ayatollah Ali al-Sistani emphasized his support for the demonstrators in his weekly Friday sermon, saying none of their demands have been met so far and that electoral reform should be a priority. The senior cleric called for a new election law that would restore public confidence in the system and give voters the opportunity to bring “new faces” to power.

But Iraqi authorities appeared determined to disperse the protesters and keep them confined to a shrinking space in the capital’s center.

The confrontations in Khilani Square began on Friday afternoon after hundreds of protesters who breached the concrete barriers streamed into the square, where they were met by soldiers and riot police.

Around 5:30 p.m., live rounds were heard by The Associated Press several hundred meters from the square, and shortly after wafts of stinging tear gas caused a mass of protesters to run toward the medical tents.

Iraqi security and medical officials, who requested anonymity in line with regulations, said three protesters were killed and at least 25 others wounded.

Several protesters said breaking through the barrier leading to Khilani was key to counter attempts by the security forces to suppress the anti-government movement and limit protesters to the nearby Tahrir Square.

“They are trying to limit us to one place,” said Nashat Akram, 24, recovering in a medical tent in Tahrir square.

The atmosphere at Tahrir was a striking contrast with the violence nearby. Baghdad’s main square has been transformed into a carnival-like hub where protesters gather around music, comic art installations, pop-up food and street shops.

The demonstrations have kept up for weeks in central Baghdad and the mostly Shiite southern provinces, despite the clamp down by Iraqi security forces.

Al-Sistani, whose opinion holds major sway over Iraqis, said a fair electoral law should give voters the ability to replace current political leaders.

“If those in power think they can evade dealing with real reform by procrastination, they are mistaken,” al-Sistani said.

He said corruption among the ruling elite has reached “unbearable limits” while large segments of the population are finding it increasingly impossible to meet basic needs.

On Monday, al-Sistani said he backed a roadmap by the U.N. mission in Iraq aimed at meeting the demands of the protesters, but expressed concern that political parties were not serious about carrying out the proposed reforms.

Associated Press writer Murtada Faraj contributed reporting.