QUITO, Ecuador (AP) - A volcano near this Andean capital spewed a mushroom-shaped cloud of smoke Thursday, prompting officials to warn that a potentially dangerous ash rain may be imminent. The release of smoke from the Guagua Pichincha volcano came a day after an 89-year-old man died as a result of respiratory problems worsened by the volcanic dust, according to the Red Cross. Dozens of people required medical assistance, and authorities ordered schools closed until the threat posed by falling ash passes. The towering cloud that emerged Thursday was believed caused by several gas explosions inside the 15,850-foot volcano. The smoke emerged slowly and was clearly visible from almost anywhere in Quito under a clear sky.