MANILA, April 8 (Xinhua) -- Bulusan Volcano in the central Philippines exploded before dawn on Sunday, while Taal Volcano near the capital showing obvious signs of unrest, a local radio reported.

    Residents of Casiguran town in Sorsogon province, where Bulusan Volcano sits, were surprised after they got a glimpse of the explosion that sent ash up to five kilometers high, radio dzRH reported.

    "It's a cruel Easter greeting. It had kept quiet for three weeks, then exploded just like that," Casiguran town Mayor Edwin Hamor said in an interview on the radio.

    Hamor said he has alerted at least five villages in the town south of the volcano to take precautions, including using towels and face masks to protect themselves from the ash fall.

    Philippine Institute of Volcanology and Seismology (Phivolcs) said it observed the Bulusan explosion at 5:45 a.m. on Sunday. The volcano authority said that residents within the volcano's four-kilometer permanent danger zone have to move out of the area.

    Meanwhile, the Phivolcs also raised the alert against venturing near Taal Volcano in Batangas, some 80 kilometers to the south of Manila, the radio report added.

    Phivolcs director Renato Solidum said Taal had been showing "much abnormality" in past days. "The crater is hot and bubbling. People should not venture near the crater area," he said.

    The Philippines sits on a seismically unrest stretch of the Pacific Ocean known as the "Ring of Fire", with a total of 22 active volcanoes in its territory.