BEIRUT — Lebanese authorities on Tuesday detained Riad Salameh, the country’s disgraced former central bank governor, after an investigation into his financial dealings with a Lebanese brokerage firm, the state-run news agency reported.

       Salameh, who served as the head of Banque du Liban for three decades and was credited with reviving Lebanon’s post-civil-war economy, left his post under a cloud more than a year ago. He was blamed by many for the stunning collapse of Lebanon’s banking sector and was under investigation, along with relatives and associates, for a farrago of financial corruption charges by authorities at home and abroad, including in France.