Lava spewing from a continuously erupting volcano in Hawaii has blocked a highway that serves as a major evacuation route.<br />The first serious injury has also been reported as Mount Kilauea becomes more violent.<br /> A man sitting on a balcony was hit in the leg by a projectile of molten rock - otherwise known as lava spatter.<br />Some are said to weigh as much as a refrigerator. <br /> The lava stream, meanwhile, has blocked Highway 137 and threatens to make other escape routes inaccessible. <br />It is also flowing into the ocean prompting warnings of laze - clouds of hydrochloric acid and steam filled with fine glass particles formed when hot lava hits ocean water. <br />
