Whitehorse RCMP believe a man accused of sexually assaulting a woman last Thursday may have fled the territory and are asking for the public's help in tracking him down.

Stephan Keene has been charged with sexual assault and forcible confinement in regards to the early-morning incident, according to police.

The attack allegedly took place in the building where both Keene and the woman were staying, Sgt. Don Rogers said today.

The two did not know each other, but were neighbours in a "rooming house, apartment-style place,” Rogers said.

The sergeant would not name the exact location, he said, because the woman may still be living there.

"It was a crime of opportunity more than a predatory attack where someone was laying in wait,” Rogers said.

Although the woman contacted police last Thursday, police had to wait for a warrant to be issued for the 35-year-old suspect before they could release his name to the public, Rogers explained.

Police are not releasing any other details about the incident, but are asking anyone with information on Keene's whereabouts to contact the Whitehorse detachment.

"He's a bit of a wanderer,” Rogers said of Keene. "He's lived in a number of provinces – I think Ontario and British Columbia – so we don't know where he's headed.”

Keene is described as a white male with blonde hair. He is six feet three inches tall (192 cm) and weighs approximately 180 pounds (80 kg).

He has no fixed address, according to police, and is not normally a resident of the Yukon.

"But in the short time he was here, we knew him,” Rogers said.

Keene is not believed to have his own vehicle, police said.