A high-risk Yukon sex offender is at large after he walked away from the Vancouver-area halfway house he was staying at on Sunday afternoon, say Vancouver police.

Marcellus Norman Jacob, 27, is wanted Canada-wide for breaching the Corrections and Conditional Release Act. Police have advised anyone who sees Jacob to call 911.

Jacob was released to the halfway house in May after serving two-thirds of a seven-year jail sentence for break and enter and assault.

Jacob was previously released on parole last February, but his parole was revoked after he failed to return to the Vancouver halfway house he was ordered to live at. He turned himself into police four days later.

Jacob walked away from the halfway house at 5:30 p.m. Sunday, according to police.

He is a five-foot, four-inch-tall aboriginal man, weighing 169 pounds with dark spiky hair. He was last seen wearing a red sweater, black pants and black runners.

Jacob has been sexually violent toward both adult and teenage females, and has a long history of violent and property-related offences. He is considered to be a high risk to reoffend sexually or violently. Alcohol and drugs have been significant factors in his past offences.

The conditions attached to Jacob's release in May required him to:

• follow psychological counselling;

• live at a community residential facility;

• report all relationships with females to his parole supervisor;

• abstain from all intoxicants;

• have no contact with his victim or her family; and

• have no contact with anyone under 16 without being accompanied by an adult who is pre-approved in writing by his parole supervisor.

As part of the residency condition, overnight leave will not be allowed due to Jacob's high risk to the community, says the National Parole Board's decision from May.

"You are serving your first federal sentence of seven years for break and enter and committing sexual assault with a weapon," reads the decision directed at Jacob.

"At the age of 21, you broke into a (Whitehorse) woman's home and, over several hours, raped and tortured her at knifepoint. You threatened to kill her if she reported your sadistic actions."

The incident occurred in July 2001.

The decision also listed Jacob's history of property offences, violence and "a long and troubling history of sexually-deviant behaviour towards both males and females and persons younger, same-aged or older than you."

Listed as a moderate to high risk to re-offend both violently and sexually, Jacob's personality traits are also considered a major risk factor, it's noted.

"Females, especially young females, are likely to be your future victims," the report reads.

Jacob completed several programs while incarcerated, including anger management and cognitive skills, and reports suggest he's gained awareness of risk factors.

However, given the problems since finishing the programs, it's doubtful there's been enough progress that would prevent him from being a threat to the community, the decision stated.

"Your institutional behaviour has been problematic, with angry outbursts, although it has improved," the report reads.