It is the fourth operation of its kind this year from the camp, which lies less than 10 kilometres (six miles) from the Iraqi border.

In the latest transfer, around "620 people, relatives of IS members, left Al-Hol", coordinated between the camp administration and the Iraqi government, the Syrian Observatory for Human Rights said in a statement.

The men, women and children belonged to 150 families and left the camp on Thursday, an official in the Kurdish administration told AFP.

Thousands of foreign extremists joined IS as fighters, often bringing their wives and children to live in the "caliphate" declared by the group across swathes of Iraq and Syria in 2014.

Kurdish-led forces backed by a US-led coalition dislodged the jihadists from their last scrap of territory in Syria in 2019.

Kurdish authorities have repeatedly called on countries to repatriate their citizens from crowded displaced camps, of which Al-Hol is Syria's largest.

More than 100 people, including many women, were murdered in Al-Hol over an 18-month period, the United Nations said in June, calling for camp residents to be returned home.

But nations have mostly received them only sporadically, fearing security threats and a domestic political backlash.

The first repatriation of Iraqi families from Al-Hol, involving around 300 people, took place in May last year.

Iraq should repatriate 500 families in total from Al-Hol this year, the official Iraqi New Agency announced on Wednesday.

In addition to the returned family members, the Iraqi government also received this week about 50 Iraqi IS fighters and leaders who were detained by the Syrian Democratic Forces, according to the Observatory.

The SDF spearheaded the fight against IS in Syria with the support of the US-led coalition.

In early June, Iraq repatriated another 50 Iraqi IS fighters who were detained by Kurdish forces. They were among 3,500 Iraqis held in Syrian Kurdish prisons, a senior military official said at the time.

In April, a senior Iraqi security official said the Al-Hol camp is a security threat and should be dismantled.

It houses around 55,000 people, the United Nations reported in June.