An explosion at a US-Canada bridge in Niagara Falls claimed two lives, prompting closure of four border crossings. Details on the cause remain elusive, sparking concerns on both sides. Canadian PM Trudeau termed it "extraordinarily serious," and President Biden closely monitored developments. The blast occurred on the US side of the Rainbow Bridge, leading to closures and heightened security measures. Investigations are ongoing, and witnesses described a vehicle crashing and exploding, causing a fiery scene.
