"We opened a safe passage to protect the people of Sinjar and we started transferring them to West Kurdistan," PKK spokesman Bakhtiar Dogan told AFP.

West Kurdistan refers to the separatist Kurdish region of northern Syria which borders Turkey and Iraq.

"We engaged Daash (Islamic State) fighters several times and are ready to keep fighting for the sake of our people," he said, without specifying how many families had been rescued.

Kurdish fighters from Iraq, Syria and Turkey appeared to agree earlier this week to share the burden of containing IS fighters who have been making significant gains in northern Iraq lately.

An attack the jihadists launched at the weekend on the Sinjar region, east of their main Iraqi hub of Mosul, forced tens of thousands of people to run from their homes in panic.

Many of them are from the Yazidi minority, a closed community which follows a 4,000-year-old faith and which the Islamic State refers to as "devil worshippers" due to their unique beliefs and practices.

Thousands of them are believed to remain stranded in the nearby Sinjar mountains, with little food or water, facing the double threat of jihadists and starvation.

Turkish officials said that at least 800 Yazidis have made their own way to Turkey since Wednesday.

Bakhtiar Dogan confirmed that "any of those who crossed into Turkey probably got there by themselves because those who fled through our safe passage and with our assistance went to Syrian Kurdish towns."

The Sinjar mountains are a barren range stretching over around 60 kilometres (35 miles), with a peak at nearly 1,500 metres.