Hundreds of villagers fled to safety Monday after a restive volcano belched ash and smoke into the sky after a monthlong lull, officials said.

Despite Mount Bulusan's ash explosion, its 13th since November, there were no signs of an imminent eruption involving magma pushing out of the cone, said government chief volcanologist Renato Solidum.

The huge plume of grayish smoke shot up to more than a mile (2 kilometers) toward the blue sky, with the ash drifting southwest toward four farming towns in Sorsogon province, where about 1,200 villagers fled to emergency shelters and houses of relatives, said Benito Ramos, who heads the government's disaster-response agency.

Army trucks helped villagers move from communities hit by the ashfall and emergency teams handed out protective masks, Ramos said.

There have not been any government orders to evacuate communities near the mountain. While many scrambled to safety, residents streamed out of houses in Irosin town to gaze or take pictures of the mid-morning spectacle using their cellphones.

Still-hot debris at the peak of Bulusan, one of the country's 23 active volcanoes, came into contact with water, sparking the explosion. Such steam-driven blasts have happened since November and could continue in coming weeks, Solidum said.

Bulusan lies about 240 miles (380 kilometers) southeast of Manila.