Manila - The most active volcano in the Philippines was showing signs of increased activity that could lead to an eruption, government scientists warned on Sunday.
They raised the alert level at the Mayon Volcano in Albay province, 330 kilometres south-east of Manila, to level 2 on August 15.
Since then, experts have monitored an increased number of earthquakes, including a rock fall event in the past 24 hours, an increase in sulphur dioxide emissions and persistent ground swelling, indicating that magma was rising to the surface.
In May 2013, Mayon suddenly ejected smouldering rocks and ash into the air, killing three Germans, a Spanish hiker based in Germany and a Filipino guide.
The 2 472-metre volcano, famous for its almost-perfect cone, has erupted about 50 times since 1616.
Mayon's most violent eruption was in 1814, when more than 1 200 people were killed and a town was buried in volcanic mud. An eruption in 1993 killed 79 people. - Sapa-dpa