The daylight murder of a 27-year-old woman has many people thinking twice before venturing onto the capital's normally peaceful network of walking trails and bicycle pathways.
A killer is on the loose and women are being warned against solitary walks or bike rides in area parks.
Summer biking or walks along the waterfront or through wooded areas are about as traditional in Ottawa as skating the Rideau Canal in winter.
But on Monday a police dog found the body of Ardeth Wood.
Her body was discovered hidden in thick, grassy underbrush near a creek where police divers earlier found her bike.
Ms. Wood, 27, a doctoral student, left her parents' suburban Ottawa home last Wednesday for a noon-hour bike ride, but never came home.
She was on a two-week study break from the University of Waterloo when she disappeared.
"There's obviously a very sick individual on the loose at the moment. It might be a wise idea to travel with a friend," said Jennifer Allen, spokeswoman for Ottawa's Citizens for Safe Cycling.
Ottawa police released a composite drawing of a man in his early 20s, about five feet, 11 inches tall, with sandy hair, a muscular lean build and tanned skin.
A man matching that description was reported approaching women near the area where Ms. Wood disappeared, said police, who have not said if the crime involved a sexual assault.
Criminologist Neil Boyd said the apparent randomness of Ms. Wood's murder contributes to the fear gripping.
"It is fair to say that this is a crime that is extremely unusual for Ottawa," said the Simon Fraser University professor.