Jorge Sosa, 55, was arrested in Alberta in 2011 and on Monday he was sentenced to 10 years for lying on his U.S. citizenship papers about his alleged role in the killings. At least 160 people were killed in the village of Dos Erres in 1982.
Sosa had both Canadian and U.S. citizenship when he was arrested in Lethbridge, Alta., and then extradited. U.S. District Court Judge Virginia Phillips stripped Sosa of his U.S. citizenship after handing down her sentence.
"Although we would have liked to have seen Sosa tried for war crimes, the fact that he got a 10-year sentence and will be spending several years in prison is a step in the right direction," Matt Eisenbrandt, legal director for the Canadian Centre for International Justice, said from Vancouver.
"We hope that someday he will be put on trial for war crimes and crimes against humanity to really get accountability for the Dos Erres massacre."
The Centre for International Justice had launched a campaign before Sosa's extradition to the United States to encourage the Canadian government to keep him and try him for war crimes.
Eisenbrandt said there is every reason to believe that Sosa will be deported to Guatemala once his sentence in the U.S. is complete.
"They almost certainly will," he said. "The other thing the judge did was revoke his U.S. citizenship almost immediately and essentially seemed to indicate he would likely be deported after his sentence."
Sosa is wanted by Guatemalan authorities for the Dos Erres killings. The military unit believed the village was under rebel control and that its inhabitants were responsible for an ambush on soldiers and the theft of 20 rifles.
Sosa's extradition proceeding heard that he was a sub-lieutenant at the Kaibil School, which trained special commando units in Guatemala in the late 1970s and early 1980s, and was one of the commanders of a 60-man unit that surrounded Dos Erres in December 1982.
Many of the villagers were killed with sledgehammers. The women and girls were raped and their bodies thrown down a village well, the hearing heard. No stolen weapons were found.
Sosa has denied being in the village that day.
A former member of the same unit, Pedro Pimentel Rios, was extradited from the United States to Guatemala and sentenced to 6,060 years in prison for his role in the killings.
— By Bill Graveland in Calgary with files from the Associated Press. Follow @BillGraveland on Twitter.