A truck driver was killed and all lanes of the northbound Northway between exits 17 and 19 closed by a crash involving two tractor-trailers early Wednesday. Both trucks burst into fire after they collided near the Exit 18 overpass, and one driver was able to free himself and escape his cab while the other was not, officials said. State Police said one of the trucks was stopped on the highway’s shoulder when it was hit by the other around 3:30 a.m. The driver of the stationary truck escaped but the other died at the scene. Their names were not immediately released, as police were working to identify the man who died. The surviving driver suffered minor injuries and was treated at the scene by West Glens Falls Emergency Squad members.