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.