Police in the central Vancouver Island city say they responded to a complaint on Tuesday and found a woman breathing but unconscious in an alley and a man hiding in nearby bushes.
They say the man ran away, the woman was taken to hospital, and police called in Boomer who bounded across backyards and over fences before apprehending the suspect.
Police say the man was treated in hospital for dog bites suffered in the pursuit and is now in custody, and the woman did not suffer any serious injuries.
However, police say she may have ingested the so-called date-rape drug as officers found a milk jug at the scene that contained a liquid believed to be GHB.
Mounties say a 43-year-old man is charged with breaching his bail conditions for allegedly having contact with the woman and possessing or consuming drugs or alcohol.
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