Scientists in the Philippines say they expect Mount Mayon to erupt at any time. The volcano has been emitting lava and ash for days.
Security forces have set up an 8km exclusion zone around the volcano and have ordered people to evacuate the area.
About 40,000 people have moved to temporary evacuation shelters, but officials have estimated that several thousand are still within the danger zone, unwilling to leave their farms and livestock.
Police have recently stepped up their enforcement of the exclusion zone, and have had to escort some people from the area.
Evacuations began when the volcano became more active last week. On Sunday, the number of volcanic earthquakes more than doubled, signalling an eruption is possible within days.
Mount Mayon last erupted in 2006, when it expelled lava and steam for two months.
The volcano has erupted 48 times since records began, but the most violent one was in 1814, when more than 1,200 people were killed and several towns destroyed.
The volcano is about 330km (206 miles) south-east of the capital Manila, near Legazpi city in Albay province.
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