The arrests came during early morning raids in Ankara's Mamak and were carried out by anti-terrorism units, Today's Zaman reported.
Officials said a large number of documents believed to be linked to the Revolutionary People's Liberation Party/Front (DHKP/C) were found during the raids and have been seized.
On Tuesday, unidentified assailants threw two grenades into the annex of the Ministry of Justice and another group attacked the ruling Justice and Development Party's headquarters using a light anti-tank weapon.
No one died during the attacks, however one person was slightly injured.
Exploding whale video goes viral on Internet
N.J. man wakes up from 10-hour sleep with knife in back