US and Estonian officials say they have identified the ringleaders of one of the most advanced criminal hacking rings operating today, apprehending an Estonian accused of helping orchestrate a $9m theft.

Sergei Tsurikov, 25, of Tallinn, was arrested by Estonian authorities and faces extradition, a rare triumph for US authorities frustrated by Eastern European hackers. Mr Tsurikov was named in a federal indictment on Tuesday as co-ordinating the efforts of a Moldovan man who found the vulnerability in the RBS system and a Russian who best knew how to take advantage of it.