Turkish warplanes strike militant targets regularly in the region in their battle against Kurdistan Workers Party (PKK) guerrillas, and have stepped up raids after a PKK attack in August.
"We have 30 corpses, all of them are burned. The state knew that these people were smuggling in the region. This kind of incident is unacceptable. They were hit from the air," said Fehmi Yaman, mayor of Uludere in Sirnak province.
The pro-Kurdish Peace and Democracy Party (BDP) said in a statement 35 people had been killed, adding that party leaders were heading for the area.