ANKARA (Reuters) – Turkey has asked Germany to extradite a theology lecturer suspected of playing a major role in last year’s failed coup, Foreign Minister Mevlut Cavusoglu said on Wednesday.

Turkey sent a diplomatic note requesting the extradition of Adil Oksuz, who the government says was the “imam” of air force personnel who last year bombed parliament as part of the attempt to topple the government.

Authorities say Oksuz was detained near an Ankara air base hours after the coup attempt, only to be released by a judge two days later and has been on the run since. Turkish media have reported that he has been spotted in Frankfurt and Ulm and given a temporary residence permit by Germany’s Baden-Wurttemberg state.

“We sent a diplomatic note to Germany after the news regarding the presence in Germany of the FETO suspect Adil Oksuz, who is currently at large,” Cavusoglu told broadcaster TRT Haber in an interview.

FETO is the government’s label for supporters of the U.S.-based cleric Fethullah Gulen who authorities say was behind the coup attempt.

Video footage released after the coup attempt showed Oksuz and businessman Kemal Batmaz, another alleged ringleader in the coup attempt, arriving at Istanbul’s main airport two days before the attempted putsch.

Authorities say the men were returning from a visit to the United States where they allegedly met Gulen. The cleric, who denies involvement in the attempted putsch and has condemned it, has lived in self-imposed exile in Pennsylvania since 1999.

Batmaz remains in detention after his arrest in the immediate aftermath of the failed coup.

More than 50,000 people have been detained and 150,000 have been suspended in the crackdown that following the attempt. Journalists and opposition figures have also been targeted.

The scale of the crackdown has strained ties with some of Turkey’s allies, such as Germany, which have voiced concern that President Tayyip Erdogan may be using the coup as a pretext to quash dissent.

Ankara says such measures are justified by the threat to democracy now posed by Gulen, a former Erdogan supporter. More than 240 people were killed in the coup, most of them civilians.

(Reporting by Ece Toksabay and Dirimcan Barut; Writing by David Dolan; Editing by Dominic Evans)