Police in northwestern Ontario took a new tack in their investigation Friday into the disappearance of a Toronto woman, and began interviewing everyone who lives in the vicinity of the rugged provincial park where she was last seen.

Searchers have been scouring the Rainbow Falls Provincial Park near Schreiber for 11 days for any sign of Christina Calayca.

Christina Calayca was last seen jogging near Rainbow Falls Provincial Park on the north shore of Lake Superior on Aug. 6.Christina Calayca was last seen jogging near Rainbow Falls Provincial Park on the north shore of Lake Superior on Aug. 6.
(Canadian Press)

Calayca, 20, was last seen on Aug. 6 as she went for a jog near the entrance of the park, on the north shore of Lake Superior about 200 kilometres east of Thunder Bay.

Investigators are also talking to everyone camped at the park around the time of her disappearance.

OPP Chief Supt. Mike Armstrong said detectives are just following protocol.

"Every time there's a lost person, we do a parallel criminal investigation, and we're doing that in this case," Armstrong told CBC News. "But I can tell you there's no evidence of foul play here."

Calayca is still considered to be somewhere in an eight-kilometre radius of the park, Armstrong added.

"We're continuing to assess what do we have left to cover, [and] what areas we have that we haven't covered the way we want," he said.