MANILA, Philippines (AP) — The Philippines' most active volcano belched out huge lava fragments that rolled about a kilometer (half a mile) down its slope in an ongoing gentle eruption, prompting authorities to evacuate thousands of villagers, officials said Tuesday. 
 
 The Philippine Institute of Volcanology and Seismology raised the alert level for Mount Mayon, warning that a "hazardous eruption" is possible within weeks. Increased restiveness was recorded overnight, including the ejection of glowing rocks from the summit and dozens of low-frequency volcanic earthquakes. 
 
 Molten lava has accumulated at the top of the 2,460-meter (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 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 Monday, when thick clouds parted and revealed the volcano's summit. He said the fragments could be seen from as far as 12 kilometers (7 miles) away. 
 
 Mount Mayon, a popular tourist site known for its near-perfect cone, lies in coconut-producing Albay province, about 340 kilometers (210 miles) southeast of Manila. 
 
 Albay Gov. Joey Salceda ordered the evacuation of up to 12,000 residents within an 8-kilometer (5-mile) radius of the volcano's crater. Villagers within 6 kilometers (4 miles) of the volcano, which the government has declared a permanent no-go danger zone, face mandatory evacuation. 
 
 Disaster-response officials convened an emergency meeting Tuesday to map out steps to avert casualties. They have been concerned over a brewing storm in the Pacific that might hit the country, including Albay, in a few days, adding possible deadly volcanic mudflows called "lahar" to their worries. 
 
 "Thousands have been evacuated since last night," Cedric Daep, a safety officer in Albay, said by phone. 
 
 Mayor Herbie Aguas said his farming town of Santo Domingo, among the closest to the volcano, has a frightening legacy from Mayon. The volcano nearly wiped out the municipality's 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. 
 
 "We are praying that it would not be the worst-case scenario," Aguas said, adding that nearly 4,000 of the 40,000 residents in his town who live within a government-declared danger zone had 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 government-declared permanent danger zone. 
 
 Villagers living near the volcano have erected huge white crosses at the entrance of their neighborhoods, hoping they will protect them from harm. 
 
 On May 7, 2013, the volcano suddenly spewed ash, killing five climbers, including three Germans, who had ventured near the summit despite warnings of possible danger. 
 
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 Associated Press writers Oliver Teves and Jim Gomez contributed to this report. 

 Media playback is unsupported on your device Media caption Mount Mayon has erupted dozens of times since records began 
 
 A volcano has erupted in the Philippines, killing four German climbers and their guide. 
 
 Mount Mayon, 330km (206 miles) south-east of the capital Manila, sent a cloud of ash and rocks into the sky early on Tuesday. 
 
 The ash blast caught a group climbing the mountain, which is famous for its near-perfect cone. 
 
 At least seven other climbers were hurt in the eruption, which lasted for just over a minute. 
 
 "Five killed and seven are injured, that is the latest report," National Disaster Risk Reduction and Management Council chief Eduardo del Rosario said. 
 
 Four of those killed were German nationals and the fifth was their Filipino guide, the NDRRMC said later in a statement. 
 
 A guide on the mountain told a local television station by telephone that those who died were hit by the rocks that rained down on them after the ash blast. 
 
 Twenty people were approaching the summit of the mountain when the eruption occurred. 
 
 "It was so sudden that many of us panicked," Jun Marana, a local resident, told AFP news agency. "When we stepped out we saw this huge column against the blue sky." 
 
 In an advisory, the Philippine Institute of Volcanology and Seismology called the eruption a "small phreatic event" that lasted about 73 seconds and sent ash 500m into the air. No intensification of volcanic activity was observed, it said, and the alert level would not be raised. 
 
 But it said small steam and ash ejections could occur with little or no warning and advised against entry to the 6-km (4-mile) radius Permanent Danger Zone around the volcano. 
 
 Chief state seismologist Renato Solidum described the eruption as a "stream driven explosion", a "normal process" in any volcano. There was no need for local residents around the mountain to evacuate, he said. 
 
 Mt Mayon has erupted at least 48 times since records began. The most violent eruption, in 1814, killed more than 1,200 people and devastated several towns. 
 
 The most recent eruption was in late 2009, when tens of thousands of local residents were forced to evacuate as the volcano rumbled back to life.
– More than 12,000 residents were evacuated from the foot of Mount Mayon in the Philippines today as the volcano spewed out lava that spilled a half-mile down the mountain and glowed ominously from the crater at its peak, the AP reports. Joey Salceda, governor of the Albay province, ordered the evacuation of everyone within a 5-mile radius of the crater, while the region within 4 miles of the volcano was declared a "permanent no-go danger zone." His order came on the heels of the Philippine Institute of Volcanology and Seismology raising the alert status to Level 3, indicating that a "hazardous eruption" could take place within weeks, Yahoo Philippines reports. The area had already been experiencing quakes and falling rocks, Reuters reports. The volcano, located slightly more than 200 miles southeast of Manila, is known around the world for its nearly perfectly shaped cone—but also for its tumultuous temperament. It has erupted 50 times over the past five centuries, notes the AP, including a devastating 1814 eruption that killed more than 1,200 people, the BBC reports. Locals have even taken to putting up white crosses to ward off bad luck, according to the AP, but officials aren't banking on superstition-driven preemptive strikes to keep the lava at bay. "It's already erupting, but not explosive," says an institute official. "Currently, the activity is just lava coming down. [But] if there is an explosion, all sides of the volcano are threatened."