August 7, 2006—For weeks, beautiful flows of lava on the slopes of the Phillipines' Mayon volcano have enraptured onlookers. Here, villagers and sightseers watch on August 1 as the volcano undergoes a mild eruption.

Photo by AP.

But it's far past time to leave.

The volcano sent six plumes of ash high into the air today, prompting officials to intensify eruption warnings and step up evacuations near the mountain, located in southern Luzon about 200 miles (325 kilometers) southeast of Manila (map of Philippines).

Saying an eruption is imminent, the government raised the alert for the 8,000-foot (2,500-meter) volcano to level four—the second-highest level—from level three.

Officials also extended the "danger zone" on the mountain's south side to 5 miles (8 kilometers) from 4.3 miles (7 kilometers).

Last week, the government deployed troops to help evacuate the sightseers. Now 35,000 villagers are being moved out, Gov. Fernando Gonzalez of Albay province told the Associated Press, and 20,000 more will be evacuated if a major eruption occurs.

Lava has been flowing down Mayon since July 14, but activity has strengthened in recent days. Volcanologists have detected 21 low-frequency volcanic earthquakes since early Sunday morning, the AP reported.

Famous for its near-perfect cone shape, Mayon is the Philippines' most active volcano, according to NASA's Earth Observatory. The mountain last erupted in 1993, killing more than 70 people.

—Aalok Mehta