Lava glows while cascading on the slopes of Mayon volcano as seen from Lingnon Hill in Legazpi city, 500 km (310 miles) south of Manila December 15, 2009. Philippine authorities started evacuating about 50,000 people from around the country's most active volcano on Tuesday as it spewed burning mud and rocks. Mayon volcano, famed for its near-perfect cone shape in a coconut-growing region of the central Philippines, started to release lava early this week and vulcanologists are expecting a major eruption in the next few days. REUTERS/Erik de Castro (PHILIPPINES - Tags: ENVIRONMENT IMAGES OF THE DAY)