Police investigators found 20 bone fragments on Monday during a dig at a site near the town of town of Cizre.
Turkish police detained five people on Tuesday after finding bone fragments detectives think may be the remains of victims of extrajudicial killings in the mainly Kurdish southeast, state-run Anatolian Agency (AA) said.
Police investigators found 20 bone fragments on Monday during a dig at a site near the town of town of Cizre, some 40 miles from the Iraqi border, the news agency said.
Authorities are still searching for a former mayor of Cizre whom they suspect is linked with the find, Anatolian said.
Turkish newspapers have said police are acting on information from suspects in a probe of the so-called Ergenekon group, which allegedly plotted to overthrow the government.
Hundreds of Kurdish civilians went missing in the 1990s during the height of a conflict between the Kurdistan Workers Party (PKK) guerrilla group and the Turkish state that has claimed more than 40,000 lives, mainly Kurdish.
Police think the bones discovered on Monday are the remains PKK sympathisers who were killed by Hizbullah, a radical Islamist group active in southeastern Turkey during the 1990s, Anatolian said.
Hizbullah, which is not linked to Lebanon-based Hezbollah, is believed to have been armed by the state to fight PKK guerrillas.