Former Colombian President Álvaro Uribe has been found guilty of witness tampering and bribery charges in a historic trial that gripped the South American nation and threatened to tarnish the conservative strongman’s legacy.

Former Colombian President Álvaro Uribe Vélez was convicted Friday of bribing a witness and procedural fraud, following several hours of sentencing in a case that spanned more than a decade.

Mr. Uribe, a towering figure in Colombian politics, was accused of trying to bribe a former paramilitary to retract testimony damaging to him.