Santiago, Rajab 4, 1436, Apr 23, 2015, SPA -- Two explosions from the Calbuco volcano in southern Chile sent huge clouds of ash into the sky, increasing worries that it could contaminate water, cause respiratory illnesses, and ground more flights. The volcano erupted Wednesday for the first time in more than four decades, and then produced another blast early Thursday. No injuries have been reported but one hiker remains missing. Authorities evacuated 4,000 people as gas and ash continued to be emitted, and they closed access to the area around the volcano, which lies near the cities of Puerto Varas and Puerto Montt, about 1,000 kilometers south of Santiago, the capital. The 2,000-meter Calbuco last erupted in 1972 and is considered one of the top three most potentially dangerous among Chile’s 90 active volcanoes. LATAM airlines cancelled flights to and from Puerto Montt because airborne ash can severely damage jet engines. --SPA 19:34 LOCAL TIME 16:34 GMT www.spa.gov.sa/w