Turkish gendarmerie forces held 401 of the migrants in Uzunköprü, Havsa and Meriç district of the northwestern province of Edirne, which borders Greece and Bulgaria.
They included nationals of Egypt, Somalia, Syria, Iraq, Afghanistan, Morocco, Iran and Pakistan.
Turkey is a key transit point for irregular migrants, who aims to cross to Europe to start new lives, especially those fleeing civil war and persecution.
336,707 irregular migrants held across Turkey in 2019, according to the official reports.
ILKHA