Saskatchewan RCMP say an arrest warrant has been issued for 50-year-old Benjamin Martin Moore, a convicted sex offender believed to be at the centre of an Amber Alert for two children.
Police say seven-year-old Luna Potts and eight-year-old Hunter Potts, along with their mother, are believed to be in South Dakota with Moore.
RCMP Chief Supt. Tyler Bates says Moore was being investigated by social services and the house where they lived was found abandoned last week.
Bates says police are looking to extend the Amber Alert into South Dakota.
He says they are extremely concerned for the safety of the children.
Mounties say they may be travelling in a 2015 dark blue Chevy Equinox.