Turkish police received a tip on a possible ISIS attack days before the jihadists' suicide bombing that killed over 100 people in Ankara four years ago.
One of the suspects in the case into the attack, Yakup Şahin, attempted to buy two tons of ammonium nitrate from a fertilizer shop in the Nizip district of the southeastern province of Gaziantep, prompting the shop owner to inform authorities, daily Cumhuriyet reported on Nov. 22, citing investigation files that surfaced four years after the attack.
Şahin is known to have escorted the suicide bombers to Ankara, where double suicide attacks targeting a peace rally that killed 103 people and wounded scores of others took place on Oct. 10, 2015.
"Is there any intelligence concerning terror related incidents in Nizip? A suspicious man asked for fertilizers from me," the shop owner said during his phone call with Nizip police on Sept. 30, 2015, adding that he didn't sell anything to the man.
Following the phone call, police examined the footage obtained from security cameras of the shop on the same day and determined the identity of the ISIS suspect.
Cumhuriyet said that police officers talked to the shop owner, who said that Şahin left upon learning that his ID was necessary to purchase two tons of fertilizer.
Nizip police then informed Gaziantep anti-terror police about the issue on Oct. 2, 2015, while asking for necessary investigations to be carried out.
In the meanwhile, the ISIS cell responsible for the attack led by Yunus Durmaz obtained explosive materials from somewhere else and hid them in a warehouse in Nizip.
Two suicide bombers from the cell were then escorted to Ankara from Gaziantep by Şahin, about whom police took no action even though his identity and suspicious activities were known.
The issue came to light when the missing files were found among the folders in a cupboard in the prosecutor's office.
Commenting on the issue, Murat Kemal Gündüz, one of the lawyers of the complainants, has said that they will file a complaint against the prosecutor for hiding nine folders of evidence.
"This massacre could have been prevented if Yakup Şahin was apprehended," Gündüz said during the hearing on Nov. 21.
The next hearing of the case will be held on Feb. 13, 2020.