SURREY, B.C. — The father of a little girl who was sexually assaulted in Surrey, B.C., papered the neighbourhood with warning letters long before police were called, says a Mountie.

Almost an entire day went by before RCMP were alerted that a six-year-old girl was sexually assaulted, Sgt. Roger Morrow said Monday.

He said the girl was walking with her 12-year-old brother and his 15-year-old male friend near their home when a man with a 15-centimetre knife ordered them into the nearby woods.

"He makes some threats against the two boys to the extent they remain where they are while he goes off into another area and this poor young six-year-old is sexually assaulted," Morrow said.

The attack happened Friday night sometime between 6 and 8 p.m., but police didn't hear about it until late Saturday afternoon.

"It's problematic," Morrow said of the delayed report of the crime. "Certainly the parents knew early evening on Friday."

Morrow couldn't say if it was an attempt at vigilante justice by the family.

"You can no doubt imagine the frustration and likely the sheer anger on behalf of the parents, likely the father ... and his desire to see this person brought before the court," he said.

Police have interviewed the boys and say the attacker is described as a darker-skinned male, possibly Hispanic, Asian or South Asian and in his late 20s or early 30s.

The Surrey RCMP detachment's Child Abuse and Sexual Offence Unit and major-crime investigators began canvassing the neighbourhood on Sunday.

Morrow stressed the importance of alerting police as quickly as possible to a crime because important evidence could be lost in the delay.

"As difficult as it can be, please ... call us as quickly as possible. Because those hours can be absolutely crucial," he said. "That being said we work with what we've got."

Morrow speaks from experience when he says there is no doubt shock would be resonating through the family, the neighbourhood, and certainly the six-year-old girl after what was a life-altering experience.

Decades ago, Morrow was attacked while coming off a transit bus when he was 12.

"I never forgot that," he said. "Maybe that's one of the reasons I'm a policeman. Because you see the need for people to address the concerns of victims."

He said people in the neighbourhood are probably questioning if they should allow their children out of their sight.

We live in a very safe community here," Morrow said of Surrey. "That being said, we do have our share of crime."

He said the odds of such a crime happening are very remote and he can't recall another such attack.

"But once is too many," he said.

Mounties issued a warning to the public about the attacker and police are working with the witnesses in hopes of drafting a composite drawing of him.