A federal jury found Allen Stanford guilty of masterminding a $7.1bn Ponzi scheme, completing an extraordinary fall from grace for a wealthy financier once feted as a successful entrepreneur.

After a criminal case that dragged on for nearly three years, a jury of eight men and four women on Tuesday convicted Stanford on 13 of the 14 charges brought by prosecutors, including fraud, obstructing investigators and conspiracy to commit money laundering. The verdict is a victory for the US government, which targeted the chairman of Stanford Financial Group as part of a crackdown on white-collar crime following the financial crisis.