Abu Hanzala, an alleged ISIL leader who declared a “holy war” against “infidels” in Turkey in 2014, has been revealed as a speaker at an Islamic conference scheduled to take place in the hearth of Turkish Capital of Ankara on February 26.

According to the posters hung around the Etimesgut district of Ankara, Hanzala is going to take the floor for a public speech and talk about “the pillars of Islam without any fear.”

Hanzala was described as “the man who has introduced Islam to hundreds of people.”

The event is organized by an extremist group called “Tevhid Ağacı.”

Hanzala, whose real name is Halus Bayancuk, initialy came to public attention after he led an Eid prayer in July 2015 in İstanbul where he criticized the Turkish government and made a call for a “holy war.” The Turkish media reported that a group of ISIL militants — allegedly consisting of 1,000 members — gathered at a picnic site in İstanbul’s Ömerli neighborhood to perform the prayers signaling the end of the holy month of Ramadan and the beginning of the celebration of Eid al-Fitr.

In Aug 2015, Turkish police conducted large-scale operations against ISIL, and detained hundreds of suspects in a counterterrorism campaign launched in the wake of an explosion in Suruç that claimed 33 lives on July 20, 2015.

As part of the investigation, Hanzala was detained in İstanbul with his wife on July 27, however; he was later arrested with several other suspected ISIL members.

Hanzala was also detained on Jan. 14, 2014, along with dozens of others during anti-terrorism raids on al-Qaeda cells by the police and gendarmerie units in six provinces across Turkey. He was later arrested. However, he was released in the eastern city of Van in October 2014 by a controversial court order after Turkey’s government removed the police chiefs who ordered the raids from office.