Ongwen was abducted by the Lord’s Resistance Army (LRA) rebel group when he was nine years old and eventually became a feared commander.

He was convicted by the International Criminal Court (ICC) in February on 61 of 70 counts of crimes against humanity and war crimes.

The crimes relate to attacks on four camps for internally displaced people in Uganda in 2004. More than 4,000 victims provided testimony in the case, which was heard in The Hague.

Ongwen was found guilty of sexual slavery, forced marriage and the rape of seven women who were abducted and placed into his household.

These charges were in addition to murder, attempted murder and torture.

The judges on Thursday said they decided not to give the maximum life sentence because Ogwen was abducted as a child on his way to primary school in the late 1980s and groomed by rebels who had killed his parents.

But they found he had knowingly committed serious crimes as an adult during the LRA’s two-decade reign of terror in the 2000s.

The judges added that they hoped to give him the opportunity to rehabilitate.

His conviction means that victims can now start the process of seeking reparations.