Vancouver police have released a composite sketch of the man who allegedly dragged a 35-year-old woman into a car in an East Vancouver alley, then stabbed and sexually assaulted her.

The attack took place at around midnight on Saturday, when the woman was walking in the east lane of Joyce Street near Archimedes Street, a few blocks south of the Joyce-Collingwood SkyTrain station.

She was approached by a man in an older-model dark bluish-green minivan that has tinted side windows and a sliding door on the passenger side.

Police say the man grabbed her and dragged her into the minivan, drove to an area near East 45th Avenue and Rupert Street, and then stabbed her and assaulted her.

"The victim managed to scream and fight off her attacker, but not before receiving serious injuries," said Vancouver Police Department​ Const. Brian Montague.

The woman was released from hospital on Monday, police said.

VPD investigators believe the man responsible for the attack is in his mid-to-late-40s, possibly Middle Eastern, with an olive skin tone and a heavy, solid build. Interviews with the victim and other witnesses put him at six feet to six feet two inches tall and weighing 250 pounds.

Police say the suspect spoke with an accent and is believed to be balding, with a short, shaved fringe of black hair around the sides and back of his head.

Officers say they have received some tips from the public, but believe others must have seen or heard something in either of those locations and are asking for those witnesses — including at least two drivers who went by East 45th Avenue near Rupert Street at around the time of the assault — to come forward.

Police are asking anyone who may know or have seen anything to contact the Vancouver Sex Crimes Unit at 604-717-0601.