Fahem al-Tai, 53, had been taking part in weeks of rallies denouncing Iraq's entrenched political elite as corrupt, inept and beholden to neighbouring Iran.

On Sunday night, he was dropped off by two friends on a motorcycle near his home, according to a neighbour.

"The area is close to the shrines, the police station, the provincial headquarters -- it's a very secure area," the neighbour said.

"He was with two of his friends when he was killed."

In footage from a street security camera seen by AFP, Tai could be seen disembarking from a motorcycle when another motorcycle with two men pulled up behind him.

The passenger could be seen shooting Tai at least twice with a pistol that appeared to have a silencer on it, before the driver also begins shooting.

The footage shows the activist collapsing and the assailants driving off.

The gunmen and a white vehicle then chased down the two activists who had dropped Tai off, according to a relative.

One of them was shot in the back but they both survived.

More than 450 people have died and another 20,000 have been wounded since anti-regime rallies erupted in Iraq's capital and Shiite-majority south in October.

They include several activists gunned down in mysterious circumstances or abducted and later found dead.

In one particularly gruesome case last week, the bruised body of 19-year-old Zahra Ali was left outside her family home in Baghdad, hours after she had gone missing.

On Friday, relatives of Zeid al-Khafaji, a 22-year-old photographer, said he had been abducted whilst returning from Tahrir Square in the capital.

Protesters have for weeks complained of being monitored, threatened and harassed in an intimidation campaign meant to keep them from pursuing their movement.

There has been minimal accountability for the casualties or the kidnappings.

Tai, married with children, had been publicly critical of other intimidation attempts against protesters.

"We will be victorious and our country will return, despite you. Despite the pain inside us, we will smile. Despite you, despite your rotten parties," he wrote on Facebook less than a day before he died.

bur/mjg/har

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