Triumphant Kurdish fighters raised their flag over the border town of Tai Abyad on Monday, dealing a huge blow to Islamic State.

A spokesman for the main Kurdish fighting force, known as the YPG also revealed they have successfully cut off a key supply road to the city of Raqqa, the de-facto capital of ISIS.

Redur Khalil said the group entered Tal Abyad - which borders Turkey and Syria - from the east and was advancing toward the west amid fierce clashes with pockets of ISIS resistance.

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Jubilant Kurdish fighters who have been battled ISIS forces in Syria raised their flag and did the victory sign over the strategically-important town of Tai Abyad on Monday after embittered fighters between the sides

Kurdish People's Protection Units (YPG) fighters take position in the northern Syrian town of Tel Abyad. A spokesman said they expect to have full control over the town within the next few hours

The Kurdish force YPG have been involved in bitter fighting against ISIS over the territory, only 80km from their de facto capital, and on Monday they were pictured waving their flag (left) and giving the peace sign (right)

Tel Abyad, near the Turkish border, is connected to Raqqa by road, which is an important supply line for ISIS

'We expect to have full control over Tal Abyad within a few hours,' he told The Associated Press in a telephone interview on Monday afternoon.

ISIS fighters holed up in the town are believed to have fled to Turkey, said Khalil, although this could not be independently confirmed.

Tai Abyad is around 80km (50miles) north of Raqqa city, an ISIS stronghold.

The success of the Kurdish fighters will make it more difficult for ISIS to bring in new foreign militants and supplies, and help the Kurdish force link up their two fronts and put even more pressure on Raqqa, whose residents are living in a constant state of fear.

But the YPG advance and intensity of fighting as caused more than 16,000 people to leave their homes and flee to Turkey in the past two weeks.

Smoke from a US-led airstrike rises over the outskirts of Tal Abyad, Syria. The Syrian Kurdish YPG militia claim to have surrounded the Islamic State-held town and cut-off the supply route to Raqqa

The fighting has led to the displacement of thousands of people, who have sought refuge in Turkey

Desperate Syrian refugees, including this mother and baby, broke through the border fence in Akcakale, southeastern Turkey on Monday as they fled the fighting that has engulfed the region

On Monday, up to 3,000 more refugees arrived at the Akcakale border crossing, according to Turkish state-run TRT television. An Associated Press photographer saw large numbers of people at the border and thick smoke billowing as U.S.-led coalition aircraft targeted ISIS militants in Tal Abyad.

The YPG has emerged as the main partner on the ground in Syria for the US-led alliance that has been bombing Islamic State in Syria and Iraq. Its advance into Raqqa province follows a campaign that drove Islamic State from wide areas of neighbouring Hasaka province

For the YPG, seizing Tel Abyad would help them link up Kurdish-controlled areas in Hasaka province and Kobani.

The expansion of Kurdish influence in Syria near the border with Turkey is a concern for Ankara, which has long been worried about separatism among its own Kurdish population.

The entrance to Suluk town near Tal Abyad after Kurdish People's Protection Units (YPG) fighters took control of the area from Islamic State fighters

YPG fighters with their weapons at the eastern entrances to Tal Abyad. They have reportedly encircled the ISIS-held town

The Kurdish units were sending reinforcements to the area south of Tel Abyad from both its stronghold in Hasaka province in the northeastern border area and from Kobani, northwest of Tal Abyad.

Fighting near the border has already forced more than 18,000 people to cross into Turkey from Syria, aid workers say. A further 5,000 are believed to have crossed on Monday, according to a Reuters photographer at the scene.

Syrians fleeing the war wait to enter Turkey near the Turkish border crossing at Akcakale in Sanliurfa province today

Thousands of people have attempted to flee the across the border to escape ISIS at Tal Abyad

Barbed wire fences keep the refugees in Syria, and they have also been blocked off by heavily armed members of ISIS

ISIS terrorists laughed with each other as they forced civilians back to the warzone even though heavy fighting at Tal Abyad is imminent

Thousands of people have attempted to flee the across the border to escape ISIS at Tal Abyad after hearing the YPG were advancing towards the town, where they fear there could be a bloodbath.

But their escape route has been blocked by heavily armed members of the terror group, who have been rounding up those trying to flee and marching them back into Syria.

Laughing Islamic State fighters have been pictured forcing desperate Syrian refugees to abandon an escape to Turkey by marching them back across the border at gunpoint.

Meanwhile, Turkish troops watched on helplessly as the civilians were almost within touching distance of the town of Akcakale.

It is thought that ISIS are keen to force civilians to stay in Syria as they fear US-led coalition forces may launch airstrikes on Tal Abyad.

If civilians still remain, they believe, the coalition would be reluctant to bomb the area.

A militant Islamist fighter waving a flag, cheers as he takes part in a military parade along the streets of Raqqa in June last year. ISIS has held the city in its iron grip since med-2013

It came before refugees waiting at the border cheered in delight as they heard that Kurdish militia were making headway towards the ISIS stronghold before attempting to battle through the barbed wire which separates Syria from Turkey.

The terror group has ruled Raqqa with an iron fist since it ousted the Syrian regime in mid-2013.

It has become the test laboratory for the extremists' hardline interpretation of Sharia despite once being one of the most secular of cities.

Women cannot leave the house unaccompanied by a man and are forced to wear the burka and face covering niqab.

Men and young boys are rounded up and sent to Sharia training camps and taught how to make and use suicide bombs and Isis' hardline interpretation of the Qur'an