Australia’s most decorated living soldier, Ben Roberts-Smith, was arrested at Sydney Airport and faces five war crimes charges related to alleged murders of unarmed civilians in Afghanistan between 2009 and 2012.

Authorities claim the victims were detained, unarmed, and under the control of Australian Defence Force personnel when they were killed.

Prosecutors allege Roberts-Smith either carried out the killings himself or ordered subordinates to do so.

Once celebrated as a national hero and awarded the Victoria Cross, he has consistently denied all allegations, Reuters has reported.

The charges follow years of investigations and legal battles, including a defamation case in which a court found multiple murder allegations against him were substantially true.