Prosecutors have said some US$4.5 billion was stolen from 1MDB – co-founded by Najib during his first year as prime minister in 2009.
In response to the ruling, Najib, who wore a dark suit and tie, said he was a victim of injustice.
“Coming from my part, I really feel it is the worst feeling to have the might of the judiciary is pinned against me in a most unfair manner,” he lamented.
After the verdict, Najib was later seen leaving the court in a black car with a police escort. A court official and a source close to Najib said he was taken to Kajang Prison, about 40 km from the capital Kuala Lumpur.