(Corrects year of Mayon's most destructive eruption to 1814)
* Fear of explosive eruption drives over 12,000 to flee
* Hazardous eruption possible 'within weeks or days'
* Lava flow reaches areas 3 km away from volcano
By Enrico Dela Cruz
MANILA, Jan 15 (Reuters) - The Philippines ordered the forced evacuation of people from two more municipalities near a restive volcano on Monday as the chief volcanologist warned of a possible hazardous eruption "within weeks or even within days".
More than 12,000 residents have already fled to evacuation centres after the 2,462-metre (8,077-foot) Mayon volcano, in central Albay province, began spewing ash on Saturday and unleashed burning mud and rocks on Sunday.
"There is an ongoing forced evacuation from the municipalities of Daraga and Legazpi because of the lava flow," Romina Marasigan, spokeswoman for the National Disaster Risk Reduction and Management Council, told reporters.
"The lava flow has reached some areas around three kilometres away from the volcano."
Mayon, a tourist attraction because of its near-perfect cone shape, showed a bright crater glow on Sunday, signifying lava had started to flow from the crater.
Manila's airport authorities said Cebu Pacific had cancelled flights to nearby Legazpi City for a second day on Monday, citing bad weather.
Philippine Airlines said it had not cancelled any flights to and from Legazpi, but there were some delays.
Mayon's most destructive eruption was in February 1814, when lava buried a town and killed 1,200 people. It last erupted in 2014, spewing lava and forcing thousands of people to evacuate.
The Philippines raised the volcano alert to level 3, which indicates increased volcanic activity toward a hazardous eruption, late on Sunday.
Level 5 indicates an eruption is in progress.
People have been advised to stay away from a 6-km (4-mile) radius Permanent Danger Zone and a 7-km Expanded Danger Zone on the volcano's southern flank.
(Reporting by Enrico dela Cruz; Additional reporting by Manuel Mogato and Karen Lema; Editing by Nick Macfie)
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