Anadolu Agency said the mayors of the towns of Savur, Derik and Mazidagi in Mardin province and the town of Suruc in Sanliurfa province were detained along with some 20 municipality officials on Friday.
The mayors, members of the pro-Kurdish People's Democratic Party, or HDP, were elected into office in March. The government accuses the party of links to the outlawed Kurdistan Workers' Party, or PKK.
Some 20 HDP mayors have been removed from office and replaced with government appointees, and 14 of them have been jailed. Seven former HDP lawmakers, including former chairman Selahattin Demirtas, are also in prison.