U.S. and Canada investigating bridge explosion at Niagara Falls border crossing

U.S. and Canadian law enforcement are investigating a vehicle explosion that occurred on Wednesday at a bridge connecting the U.S. and Canada, and are tightening border security along the U.S. northern border. Photos and video taken by bystanders and posted on social media showed thick smoke coming from the Rainbow Bridge, which connects the U.S. and Canada at Niagara Falls. They also showed flames on the pavement and a security booth that had been singed by flames. Videos showed that the fire was in a U.S. Customs and Border Protection area just east of the main vehicle checkpoint. The FBI’s field office in Buffalo said in a statement that it was investigating the blast, and investigators with the Bureau of…