Thousands of Syrians fleeing a fierce battle for the Syrian border town of Tel Abyad between Islamic State (Isis), Kurdish and opposition forces have crossed into Turkey. A Turkish official said that 6,837 people have been admitted since last week.

syrian refugees in Turkey
Turkish military use a water cannon to stop Syrian refugees as they wait behind the border fences to cross into TurkeyOsman Orsal/Reuters

Many of the refugees entering Turkey through a makeshift border crossing are women and children.

Turkish police are helping them through a break in the barbed wire fence.

syrian refugees in Turkey
Turkish soldiers help Syrian refugees as they cross into TurkeyKadir Celikcan/Reuters
syrian refugees in Turkey
Kadir Celikcan/Reuters
syrian refugees in Turkey
Kadir Celikcan/Reuters

"There are 2,000 people being processed today," the official said, adding that they undergo registration and health checks before being allowed to enter.

Tel Abyad is a key link between Turkey and the northern Syrian city of Raqqa, the de-facto capital of Isis.

syrian refugees in Turkey
Syrian refugees wait behind the Turkish border fenceOsman Orsal/Reuters
syrian refugees in Turkey
Syrian refugees wait for transportation after crossing into TurkeyOsman Orsal/Reuters
syrian refugees in Turkey
A Syrian woman is carried by Turkish soldiers to an ambulance after crossing into TurkeyOsman Orsal/Reuters
syrian refugees in Turkey
Turkish soldiers stand guard as a Syrian refugee boy waits behind the border fencesOsman Orsal/Reuters
syrian refugees in Turkey
Turkish soldiers stand guard as Syrian refugees wait to cross into TurkeyOsman Orsal/Reuters

Isis is in control of the border town in Hasaka province. The hardline group last week launched a counter-offensive in the provincial capital, Hasaka city, divided into zones run separately by the government of President Bashar al-Assad and a Kurdish administration.

The Syrian air force has bombed militant posts in a string of villages south of Hasaka, saying it had killed "tens of terrorists and destroyed their vehicles". The US-led coalition also said it has staged air strikes on IS targets in the area.

syrian refugees in Turkey
Syrian refugees carrying their belongings wait for transportation after crossing into TurkeyOsman Orsal/Reuters
syrian refugees in Turkey
Osman Orsal/Reuters
syrian refugees in Turkey
Osman Orsal/Reuters
syrian refugees in Turkey
Osman Orsal/Reuters
syrian refugees in Turkey
Syrian refugees wait for transportation after crossing into Turkey from the Syrian town of Tal AbyadAFP

The north-eastern corner of Syria is important because it links areas controlled by IS in Syria and Iraq. Syrian Kurds have also sought to expand their territorial control over a region stretching from Kobani to Qamishli which they see as part of a future Kurdish state.