ankara turkish sudanese intelligence agencies capture return turkey man believe financier u.s.-based cleric accuse orchestrate fail coup turkey state-run anadolu news agency say monday cite security source anadolu say turkey mit sudan niss intelligence agencies carry joint operation target memduh cikmaz sudan return turkey early monday cikmaz label turkish media money safe network u.s.-based cleric fethullah gulen believe transfer millions dollars gulen network sudan since flee january 2016 anadolu say sudanese officials could immediately reach comment gulen accuse ankara orchestrate fail july 2016 coup president tayyip erdogan deny involvement since abortive coup 50,000 people jail pending trial allege link gulen 150,000 people sack suspend job military public private sectors right group turkey western ally voice concern crackdown fear government use coup pretext quash dissent government say purge could neutralize threat represent gulen network say deeply infiltrate institutions army school court turkish sudanese intelligence agencies catch return allege coup suspect anadolu