Five Islamic State suspects escaped from Turkish prison this month, after being transferred to a facility with more relaxed conditions despite intelligence warnings, Hurriyet newspaper reported on Wednesday.
Three of the five were eventually recaptured, but two remain on the loose more than a week later, the report said. The search for them is ongoing and an investigation has been opened into the security lapse.
The five were arrested last year as part of raids against the Islamic State's cells in Turkey. Many hundreds of alleged members of the group have reportedly been detained in Turkey since the middle of last year, though it is unclear if they will stand trial.
The group is accused of carrying out numerous attacks, including suicide bombings in Ankara, Istanbul and southern Turkey which killed more than 150 people.