They raised pictures of Iraqi protesters who have been killed since the unprecedented anti-government movement began on October 1.

Some raised the Lebanese flag, while one woman wrapped the Iraqi tricolour around her shoulders.

Iraq's grassroots protest movement has been the largest the country has seen in decades -- but also the deadliest.

More than 420 people have been killed and 15,000 others wounded since early October, according to an AFP tally compiled from medics and an Iraqi rights commission.

The toll spiked dramatically this week, when a crackdown by security forces left dozens dead in Baghdad, the Shiite shrine city of Najaf and the southern hotspot of Nasiriyah -- the birthplace of Prime Minister Adel Abdel Mahdi, who vowed to resign on Friday.

Lebanon has also seen an unprecedented anti-government protest movement since October 17.

Layal Siblani, the organiser behind the vigil, said the spiralling crackdown in Iraq this past week prompted the idea.

"The uprising in Iraq and the uprising in Lebanon are one," she told AFP.

"A protester killed there is a protester killed here."

Like their counterparts in Iraq, Lebanese demonstrators are rallying against corruption, unemployment and appalling public services.

They are also pushing for an end to the kind of political system that prioritises power-sharing between sects over good governance.

Despite confrontations with security forces and supporters of established parties, protesters in Lebanon have largely been spared the violent crackdown seen in Iraq.

But rights groups and the United Nations last week criticised security forces for failing to protect protesters after they were attacked by backers of the Shiite Hezbollah and Amal movements at several locations.

Amnesty International on Friday urged the Lebanese army "to end arbitrary arrests" and torture of peaceful protesters following a wave of detentions.

Hussein, at the vigil on Saturday, said Lebanese protesters had a duty towards those in Iraq.

"We have to stand in solidarity with our Iraqi counterparts who are being arrested and killed on a daily basis," he said.