A lawyer representing two Vice News journalists and their assistant has denounced a Turkish court's decision to arrest them on terror-related charges, calling it a government attempt to deter foreign media from reporting on the conflict with Kurdish rebels.

The two British journalists and their Turkey-based assistant were formally arrested late Thursday in Diyarbakir, the main city in Turkey's mostly Kurdish southeast, where renewed fighting has killed scores of people.

Tahir Elci, head of the Diyarbakir Bar Association, on Tuesday said the arrests were a government move to prevent international media from reporting from the area, after Turkey earlier this year gave police heightened powers to crackdown on protesters.

A government spokesman denied the accusation and said authorities would soon make a statement on the arrests.