Turkey has denied targeting Kurdish fighters in neighbouring Syria after they claimed their poisitons had come under "heavy tank fire".

The Kurdish People's Protection Units (YPG), the armed wing of the Kurdish Democratic Party (PYD), urged the Turkish government to halt attacks after shells injured several fighters and Kurdish villagers outside an Islamic state-held town.

"Instead of targeting IS terrorist occupied positions, Turkish forces attack our defenders' positions," it said.

The alleged military strike came after Ankara began attacking IS inside Syria and offered the use of its bases to the US and its allies, but also followed attacks on Kurdish forces in Iraq.

Turkey and the United States have also been discussing a plan to set up a "humanitarian safe zone" across Turkey's border with Syria.

The issue is likely to be high on the agenda for the gathering of NATO foreign ministers on Tuesday.

A Turkish official said the claims of the attack were being investigated, but Turkish forces were only targeting IS in Syria and the Kurdistan Workers' Party, or PKK, in northern Iraq.

The official said the "ongoing military operation seeks to neutralise imminent threats to Turkey's national security and continues to target ISIS (as IS are often known) in Syria and the PKK in Iraq.

"The PYD, along with others, remains outside the scope of the current military effort."

A foreign ministry official also denied that Turkey not deliberately targeting Syrian Kurds and said the bombing of the town was "out of the question":

"Turkey has its rules of engagement - if there's fire from the Syrian side, it will be retaliated in kind," he added.

More than 1,000 people have been detained in a crackdown on militants in Turkey, with Islamic State, the PKK and the leftist DHKP-C among the groups targeted, according to Prime Minister Ahmet Davutoglu.