Police have asked for the public's help in finding suspects after a woman was sexually assaulted in north Minneapolis over the weekend.

Shortly after midnight Saturday, a woman who was walking alone was reportedly forced into a large white van by three young adults near the intersection of Golden Valley Road and Girard Avenue N., according to police.

The woman said the men sexually assaulted her before they pushed her out of the vehicle near Irving, Hillside and James avenues N.

"This is an atypical sexual assault," said Cmdr. Bruce Folkens, who oversees the special crimes investigations division for the Minneapolis police. "There are no patterns to this case that are noticed at this time."

There may have been a knife involved in the attack, which appears to have been a random "crime of opportunity," Folkens said.

The vehicle was a 12-person passenger van with a longer window on the driver's side and a set of double doors with windows on the passenger side. The middle two rows of seating in the back of the van were missing.

Investigators are looking for information on the men and the van. Anyone with information is asked to call the police tip line at 612-692-TIPS (8477).