Syrian pro-government forces have entered the Kurdish-held border enclave of Afrin, reports say, raising the risk of clashes with Turkey.
It comes a day after Syria’s state news agency said “Popular Forces” would be sent there to counter “the Turkish regime’s attack”.
Turkish troops and pro-Turkish Syrian rebels have been fighting Kurdish militia in Afrin for the past month.
Turkey has warned Syrian forces against intervening in support of the Kurds.
Syrian state TV showed pictures of pro-government paramilitaries preparing to enter Afrin on Tuesday.
Media controlled by Lebanon’s Hezbollah movement, which supports the Syrian government, and the Syrian Kurdish news agency Anha said “Popular Forces” militia had crossed into the enclave.
It is not yet clear how many fighters have moved in or where they will be deployed.
Turkey has vowed to clear Afrin of the Kurdish People’s Protection Units (YPG), which it considers a terrorist group.
Turkey sees the militia as being an extension of the Kurdistan Workers’ Party (PKK), which is banned in Turkey and has fought for Kurdish autonomy there since 1984. The YPG denies any direct military or political links with the PKK.
Kurds have run their own affairs in Afrin since Syrian forces withdrew in 2012 to concentrate on fighting rebels elsewhere in the country.
Syria’s government has called the Turkish offensive on Afrin a “blatant attack” on its sovereignty.