ANKARA, Turkey (AP) — Turkish forces have killed the alleged mastermind behind a deadly Istanbul street bombing in an operation in northern Syria, Turkey’s state-run news agency reported.

The man, identified as Halil Menci, was “neutralized” in an operation by Turkish intelligence agents, the agency said, without providing further details. HaberTurk television said the operation took place on Feb. 22 in the town of Qamishli.

The Nov. 13 bomb attack in Istanbul’s bustling Istiklal Avenue left six people dead, including two children. More than 80 others were wounded.

Turkish authorities blamed the attack on the outlawed Kurdistan Workers’ Party, or PKK, as well as Syrian Kurdish groups affiliated with it. The Kurdish militants have denied involvement.

At least 17 suspects have been jailed pending trial in connection with the attack, including a Syrian woman who is accused of leaving the TNT-laden bomb on Istiklal Avenue. Officials said at the time that the attack’s planner had fled Turkey for Syria.

The PKK has fought an armed insurgency in Turkey since 1984. The conflict has killed tens of thousands of people since then.

Turkey has launched three major incursions inside Syria targeting Syria’s main Kurdish militia since 2016 and controls a swath of Syrian territory along their joint border.