A member of the Gülenist Terror Group (FETÖ) who Sweden's Supreme Court blocked from being extradited to Turkey has been found to be one of the terror group's ringleaders.

Just weeks after Sweden signed an agreement with Turkey allowing Stockholm to join NATO as long as it take steps to address Ankara's terrorism concerns, Swedish media reports emerged recently that the court blocked the extradition of the FETÖ member, who was identified as Yılmaz Aytan, a so-called covert imam running the terror group's schools in Afghanistan.

Since 2018, Aytan has had a permanent residence permit in Sweden, where he filed for asylum to escape efforts launched against the terror group. He has since been granted refugee status, according to Swedish media.

Sweden, along with Finland, formally applied to join NATO last month, a decision spurred by Russia's war on Ukraine.

FETÖ and its United States-based leader Fetullah Gülen orchestrated a defeated coup attempt in Turkey on July 15, 2016, in which 251 people were killed and 2,734 injured.

FETÖ was also behind a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police and judiciary.

Authorities in Turkey uncovered that Aytan is a user of the organization's encrypted communication app ByLock and is among the top members of the terrorist organization.

The Turkish Justice Ministry has filed a request with Sweden to extradite Aytan for the crime of "forming/leading an armed terrorist organization."

The Swedish daily Dagens Juridik reported on Friday that the extradition of the 48-year-old man was stopped by the Supreme Court, which denied that Aytan's actions with the FETÖ terrorist group did not constitute crimes in Sweden.