The suspects were detained in simultaneous police raids in the central Anatolian city of Konya, the Anadolu Agency said.
State-run TRT television said they were suspected al-Qaeda members but gave no other details. Police would not comment.
Earlier this year, police arrested a group accused of planning to attack the US Embassy and another group in the southern city of Adana, which is home to the Incirlik Air Base used by the United States to transfer noncombat supplies to Iraq and Afghanistan. Authorities have said al-Qaeda planned to attack İncirlik in the past but was deterred by high security.
Turkish authorities have said dozens of radical militants have received training in the ranks of al-Qaeda in Afghanistan.
An attack blamed on al-Qaeda-affiliated militants outside the US Consulate in İstanbul in 2008 left three assailants and three policemen dead.