Turkish banking authorities have seized control of Bank Asya, an Islamic lender allied to an arch-foe of President Recep Tayyip Erdogan, citing a lack of transparency.
The bank has suffered major losses since last year following massive deposit withdrawals linked to a bitter feud between Erdogan and his former ally, US-exiled Fethullah Gulen.
The state-run Savings Deposit Insurance Fund (TMSF)  seized 63 percent of Bank Asya shortly after the banking watchdog (BDDK) ruled in favour of its seizure, state-run Anatolia news agency said on Tuesday.
The BDDK said in a statement on its website that it seized the bank "because the institution has not presented a partnership structure that is transparent and open enough to allow for effective regulation..."
The watchdog appointed a new board of directors immediately after the seizure.
The bank, founded by followers of Gulen in 1996, has come under pressure from regulatory restrictions, withdrawals by government-run companies and attacks from pro-government newspapers.
The pressure on Bank Asya resulted in a crash of its share price and a massive downscaling of its operation.
The bank said in November that it lost 301 million liras ($133 million) in the third quarter -- its first unprofitable quarter since it went public in 2006.
The seizure of the bank is the latest crackdown against Gulen's powerful movement known as "Hizmet", which brings together interests ranging from finance to schools to media.
Erdogan accuses Gulen and his followers of being behind a sweeping corruption probe that rocked his government in December 2013 while he was prime minister.
The president has vowed no mercy in the fight against Gulen and the authorities have over the last year effectively purged the police force and judiciary to rid them of pro-Gulenist elements.