MANILA (BLOOMBERG) - The Philippines has recorded more tremors beneath the Taal volcano island, keeping its warning that hazardous explosive eruption may happen within hours to days.

The Philippine Institute of Volcanology and Seismology recorded 486 volcanic earthquakes including four low frequency ones in the past 24 hours.

"Such intense activity likely signifies continuous magmatic intrusion beneath the Taal edifice, which may lead to further eruptive activity," it said in its 8am report on Friday (Jan 24).

The volcanology agency, in maintaining the second-highest alert, said a hazardous eruption is possible within hours or days and reiterated that total evacuation of the volcano island and other high-risk areas within the 14km radius from the main crater be observed.

On Friday morning, the volcano was releasing thick smoke, the Philippine Star reported.

Volcanology agency head Renato Solidum said the volcano 65km south of the capital Manila started releasing white steam-laden plumes past 5am local time, CNN Philippines reported. The tremors beneath the island suggests boiling of groundwater, which may exit from the volcano as steam, or an explosion can happen if there's enough pressure, he said.

The authorities this week widened an order compelling villagers to move away from the Taal volcano, including parts of popular tourist spot Tagaytay city.

The police and military on Thursday started implementing forced evacuation and total lockdown of areas within the 14km danger zone from the restive volcano, which has already sent tens of thousands of people to evacuation centres.

Taal is one of the most active and deadliest volcanoes in the Philippines, which sits on the "Pacific Ring of Fire". The volcano, which has 47 craters and lies in an island in the middle of a lake, is a top tourist attraction.