Facing the officers, demonstrators donned their equipment too -- plastic buckets, soda cans and gardening gloves.

The rivals faced off on a main bridge of the Iraqi capital, with protesters advancing from Tahrir Square and itching to reach government offices across the river in the Green Zone.

Black-clad riot police held them back, unleashing wave after wave of tear gas, but not using live rounds.

After a week of protests early this month that a national rights watchdog says ended with at least 157 dead, demonstrators came ready with their own improvised defences.

Some had gathered plastic trash bins from the streets and chased down the canisters, capping the devices with bin lids to diminish the debilitating effect of the gas.

Others put the buckets on their heads in an attempt to ward off cans that could hit them in this sensitive area.

A few donned thick gardening gloves, to pick up the searing hot containers and toss them straight back at the police, while others just kicked them away.

The best-equipped protected themselves with navy blue face masks normally used by painters.

Their less fortunate comrades fashioned makeshift devices, shearing the top off a can of Pepsi and taping it to a paper mask covering their mouth and nose.

"Now if I get hit with the gas, my eyes water a little from the gas but I won't suffocate," one protester told AFP.

Even the rainy weather was in their favour, with occasional showers and cool breezes clearing clouds of lingering gas.

The chemical agent in tear gas canisters causes severe irritation of the eyes, nose and throat, prompting coughing fits and breathing difficulties.

Soda, lemon juice and milk have been used for years by protesters around the world to lessen the symptoms.

A few Iraqis on Friday loaded up their cars with crates of soda, driving as close to the rallies as they could before security forces stopped them.

They popped open their trunks and waved over other protesters, who hoisted the crates and continued on foot to where the crowds were facing off against riot police.

"Take these to our protesting brothers," they said.

Some two dozen protesters died on Friday across Iraq, according to the Iraqi Human Rights Commission, including several hit by tear gas canisters.

Over 1,700 more were wounded across the country, most of them affected by the gas itself.

The renewed protests come after the week of rallies earlier this month, when most of the 157 who died were killed by live rounds in Baghdad, according to the rights watchdog.

This time around, security forces in the capital appeared to have orders to rely on tear gas over gun shots.

"We know how to handle this tear gas now," one protester said early on Friday.

"But we'll be afraid if they start using live rounds," he had cautioned.