A leading Iraqi anti-government activist was shot dead Sunday, security sources and activists said, sending protest movement supporters onto the streets to demand an end to such bloodshed and official impunity.

Ihab al-Wazni, a coordinator of protests in the Shia shrine city of Karbala, was a vocal opponent of corruption, the stranglehold of Tehran-linked armed groups and Iran's influence in Iraq.

He was shot overnight outside his home by men on motorbikes using a gun equipped with a silencer, in an ambush caught on surveillance cameras. His death was confirmed by security forces and activists.

Wazni had narrowly escaped death in December 2019, when men on motorbikes used silenced weapons to kill fellow activist Fahem al-Tai as he was dropping him home in Karbala, where pro-Tehran armed groups hold major sway.

Both were key figures in a national protest movement that erupted against Iraqi government corruption and incompetence in October 2019.

Around 600 activists from the movement have been killed, whether on the streets during rallies or targeted on their doorsteps.

Protests broke out in Karbala, Nassiriya and Diwaniya in southern Iraq in reaction to Wazni's killing, as people called for an end to the bloodshed and to rampant corruption.

The Iraqi Communist Party and the Al-Beit Al-Watani (National Bloc) party born out of the anti-government protests also said they would boycott Iraq's October parliamentary elections in protest.

In a video recording in the morgue where Wazni's body was initially held, a fellow activist blamed pro-Tehran groups for the killing.

"It is the Iranian militias who killed Ihab," said the activist, who was not named.

'They kidnap and kill'

"Iran out!" and "The people want the fall the regime!" chanted hundreds of mourners Sunday as they carried Wazni's body to the Shia shrines in Karbala, under a sea of Iraqi flags.

Police in Karbala said they would "spare no effort" to find "the terrorists" behind Wazni's killing.

Politicians, including Shia leader Ammar al-Haki, deplored the killing and called for justice.

Around 30 activists have died in targeted killings and dozens of others abducted, some detained briefly, since October 2019.

Such targeted killings are normally carried out in the dead of night by men on motorbikes, and nobody claims responsibility.

Activists and the UN repeatedly blame "militias".

Authorities have consistently failed to publicly identify or charge the perpetrators of these killings.

Prime Minister Mustafa al-Kadhemi took office a year ago, vowing to rein in rogue factions, fight corruption and roll out long-awaited reforms after years of war and insurgency.

He pledged again Sunday to catch "all the killers", but the latest victim's family said it would not accept the traditional visits of condolences until the assailants were unmasked.

Pro-Iran groups view Kadhemi as being too close to Washington while protesters believe he has failed to deliver on his promises.

Wazni had himself had challenged the premier in a Facebook post in February, asking: "Do you know what is going on? You know that they kidnap and kill -- or you live in another country?"

Ali Bayati, a member of Iraq's Human Rights Commission, tweeted Sunday that crimes against activists in Iraq "raise again the question about the real steps of the government regarding accountability".