The Philippines' most active volcano has sent more huge lava fragments rolling down its slopes in an ongoing gentle eruption that has prompted authorities to evacuate thousands of villagers, officials said on Wednesday.

The Philippine Institute of Volcanology and Seismology has warned that a "hazardous eruption" of Mount Mayon, located in the eastern Philippines, is possible within weeks.

Increased restiveness was recorded overnight, including 270 incidents of lava fragments and super-hot boulders rolling down from Mayon's crater — nearly four times the number recorded the previous day. Some reached the upper portion of a gully on the volcano's southeastern side, indicating that the lava dome has breached that side of the crater. The number of low-frequency volcanic earthquakes also increased.

Molten lava has accumulated at the top of the 8,070-foot volcano's crater, creating a glow in the night sky that sparked both awe and fear among spectators.

"It's already erupting, but not explosive," said Renato Solidum, who heads the government's volcano monitoring agency. "Currently, the activity is just lava coming down. If there is an explosion, all sides of the volcano are threatened."

Volcanologist Ed Laguerta said he saw huge glowing lava fragments and super-hot boulders rolling down from Mayon's crater late on Tuesday from as far as 7 miles away.

Mount Mayon, a popular tourist site known for its near-perfect cone, lies in coconut-producing Albay province, about 210 miles southeast of Manila.

The provincial disaster operations center reported on Wednesday that nearly 24,000 people from villages within an 5-mile radius from the crater had been evacuated.

The farming town of Santo Domingo is among the closest to the volcano, which nearly wiped out the entire population in an 1897 eruption with pyroclastic flows — superheated gas and volcanic debris that race down the slopes at high speeds, vaporizing everything in their path.

Today, nearly 4,000 of the 40,000 residents of Santo Domingo live within a government-declared danger zone and have started to evacuate to safer areas.

The volcano has erupted 50 times in the last 500 years, sometimes violently, endangering thousands of poor villagers who insist on living or farming in the danger zone. It is one of more than 450 volcanoes encircling the Pacific Ocean. Often referred to as the Ring of Fire, they account for about 75 percent of the world’s active volcanoes, including Hawaii’s Kilauea, which is sending lava through a vacant lot in a rural Hawaii county.

The Associated Press