Protesters regain control of third bridge in Baghdad

 Iraqi protesters regained control of a third bridge Sunday leading to Baghdad's Green Zone, taking further ground in the biggest wave of anti-government demonstrations in decades.

Security forces used tear gas and stun bombs to prevent protesters from getting right across Ahrar Bridge in central Baghdad, part of a weeks-long attempt to disrupt traffic and reach the Green Zone housing government ministry and embassies.

Protesters made a barricade of old cabinets, trash cans and metal sheeting on the bridge while security forces took positions behind blast walls installed to prevent protesters from crossing to the other side. Protesters who choked on the tear gas were evacuated by tuk-tuk, a Reuters cameraman said.

Iraqi demonstrators Saturday reoccupied part of adjacent Sinak Bridge and a nearby tall building in Baghdad that security forces had pushed them away from a week before. They have held a third bridge, Jamhuriya, since October 25.

More than 300 people have been killed since the start of mass unrest in Baghdad and southern Iraq in early October, the largest demonstrations since the fall of Saddam Hussein in 2003.

Protesters are demanding the overthrow of a political class seen as corrupt and beholden to foreign interests.

In Basra in the south, dozens of protesters burned tires and briefly blocked some roads on Sunday, before police managed to restore control and reopen them, police said.

The unrest has shattered the relative calm that followed the defeat of Islamic State in 2017.

The violence surrounding waves of anti-government protests across Iraq has been "an absolute tragedy," NATO's Iraq chief told AFP Sunday at the close of his year-long mandate.

"While the events of the last six weeks are an absolute tragedy, NATO continues to urge restraint to the government of Iraq," said Canadian Major General Dany Fortin, the outgoing commander of NATO's Iraq mission.

The year-old operation advises and trains Iraqi troops at three military schools, but Fortin said it did not have a mandate to train forces in crowd control.

Iraqi security forces have come under fierce criticism in recent weeks over their use of live rounds, machine gun fire and tear gas in response to protests.

They have been accused of firing tear gas canisters at point-blank range, leading to "gruesome" deaths and injuries when canisters pierce protesters' skulls or lungs.

The military had "atrophied" following a bloody fight to defeat Daesh (ISIS), said Fortin, describing efforts to reform it as "a generational issue."

"That takes 20 to 30 years. You're not going to see change in one year," he said.

Iraq's army was dissolved after the United States-led invasion of 2003 that toppled then-dictator Saddam Hussein.

The US then spent more than a decade helping restructure the military and the rest of Iraq's state institutions.

US, European, NATO and other forces are still deployed across Iraq to train security forces.

Fortin said NATO's operations had suffered "setbacks" in recent months, including from the protests and escalating US-Iran tensions.

Iraq has been trapped between its top two allies Tehran and Washington, who have long been at odds over the former's nuclear ambitions.

The alliance's chief, Jens Stoltenberg, told AFP in September that Tehran had been "destabilizing" the region.

Fortin will be replaced at the end of November by Major-General Jennie Carignan, who will lead roughly 580 personnel, including from non-NATO partners such as Australia, Sweden and Finland.