An American man charged with the 2006 shooting death of a Saskatoon woman was convicted of murdering a man in the United States in 1983, CBC News has learned.

George Allgood, 45, was formally charged Monday with first-degree murder in connection with the death of Susan Reinhardt, 40. 

On July 15, 2006, police were called to a home on the 800 block of 4th Avenue North, north of Saskatoon's downtown, where officers found Reinhardt and a 43-year-old man suffering from bullet wounds. Reinhardt died in hospital, but the other man survived.

Allgood, who is also facing a charge of attempted murder, was arrested last week in North Battleford, Sask. Since then, facts have emerged about his criminal past.

In 1983, when Allgood was a 22-year-old navy seaman living in Baltimore, Md., he tied up a 71-year-old man in his own home and beat him to death with a shovel. He was sentenced to 20 years in prison for the crime.

"This was a very brutal beating that resulted in the death of an elderly gentleman who lived by himself," said Warren Brown, the state attorney who put Allgood behind bars.

Brown said he was surprised to learn Allgood is now facing murder charges in Canada.

"You know, it just depends on how porous those borders are, quite frankly," Brown said. "It would seem to me, however, one sovereignty would be reluctant to allow someone with a murder conviction to set up residency."

Police in Saskatchewan said Allgood travelled back and forth between Canada and the U.S. While living in Canada, he went by the name of Reno Trevor Hogg, police said.

Sources have told CBC News that Allgood was in Saskatoon at the time of Susan Reinhardt's death and police considered him a suspect. He eventually returned to Baltimore.

The Canada Border Services Agency has rules about criminals entering Canada, but it's not known whether Allgood lied to border officials, or if he even went through a border crossing.