By Zulfiqar Ali Khan HUNZA, Feb 28: Parts of a major bridge on the Hunza river on the Karakoram Highway have been submerged by an overflowing lake formed by a landslide on Jan 4. Sources told this correspondent on Sunday that the bridge, said to be the largest on the highway, had developed cracks and was closed, cutting off Gojal valley from the rest of the country. Experts are fearing that in the event of…