MONTREAL—Items used by a three-year-old boy and his alleged kidnapper have been found on the south shore of the St. Lawrence River northeast of Quebec City in a discovery that police said is a sign the pair is alive and in the area. Quebec provincial police spent the third day searching the area for Jake Côté, who is the subject of an Amber Alert. The primary search area is around the town of Ste-Paule, Que., on the Gaspé Peninsula, where 36-year-old David Côté allegedly kidnapped his son, police said. The Amber Alert was expanded Wednesday provincewide and into parts of New Brunswick after investigators found an all-terrain vehicle believed to be used Côté. “The investigation and the searches carried out on the ground since the beginning allowed us to make the discovery of objects which were used by David and Jake Côté,” provincial police said in a news release Friday. …