Grant De Patie was dragged to his death under a car stolen by a 16-year-old.Grant De Patie was dragged to his death under a car stolen by a 16-year-old. (CBC)

The father of a B.C. man who was dragged to death while working as a gas station attendant says he's outraged after learning his son's killer failed to return to a halfway house on Friday night.

Doug De Patie said he was woken up at 2 a.m. PT on Saturday morning to a phone call from police informing him his son's killer, Darnell Pratt, had disappeared from the halfway house in Kamloops, B.C. Pratt arrived at the facility on Thursday.

"He's not taking the killing of [my son] Grant seriously," De Patie said.

"He killed Grant and Grant gave his life to stop Darnell from committing that crime that night and perhaps killing another family or someone else, and he's really thrown it back in our faces now."

Police have issued a Canada-wide warrant for Pratt's arrest.

Pratt was convicted in the 2005 dragging death of Grant De Patie, 24.

De Patie was dragged under a stolen car more than seven kilometres to his death after trying to stop a drunken Pratt from leaving the Maple Ridge station without paying for $12.30 worth of gas.

Pratt, who was 16 at the time, was sentenced as an adult.

He was sentenced to nine years in prison in May 2006 for manslaughter, but the sentence was later reduced to seven years on appeal.

Pratt was freed on statutory release this week under what the parole board said would be the most restrictive set of conditions it could impose.

The case eventually led to the creation of a law requiring drivers to pre-pay for gas in B.C.