Police in Canada and the United States say 39-year-old Robert Barnett kidnapped his 3-year-old son, Alvin Barnett, Thursday afternoon in Elk Valley, B.C.
Barnett's 2002 blue Subaru Outback was seen crossing the American border into Eureka, Mont. at roughly 3:15 p.m.
Police believe the child is in imminent danger and ask anyone who sees the pair to call 911 immediately.
Robert Barnett stands 5'5" tall and has green eyes with reddish blond hair. He has a scar about his right eyebrow and was last seen wearing a dark sweater, blue jeans and sneakers.
Alvin Barnett is 3'2" tall and has brown eyes and brown hair. He was last seen wearing a red shirt and blue jeans.
The license plate number of Barnett's car is 347SBL.