MANILA — Retailers who hoard and jack up prices of face masks will face sanctions, Health Secretary Francisco Duque said Tuesday as Taal Volcano remained under watch for a possible "hazardous" eruption.

The trade department is checking stores following reports that the retail price of face masks jumped eight-fold in the capital after Taal on Sunday belched a giant ash cloud that blanketed parts of Luzon, including Metro Manila.

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"Kapag ito ay nalamang nagho-hoard o talagang mataas ang presyo, wala na sa lugar ika nga, magkakaroon ng sanction at malilintikan itong mga nangangalakal na ito. Napakahirap na nga ng sitwasyon ng ating mga kababayan sa mga apektadong lugar, bakit naman ganoon?," Duque told DZMM.

(If it is proven that they hoarded or raised the price excessively, there will be sanctions. The situation of our compatriots in affected areas is already very difficult, why will they do that?)

N95 masks have reportedly ran out in some stores.

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Thinner surgical masks can offer enough protection in areas with light ashfall because the body has its own "air filtering system," said Duque.

The health department is monitoring 61 evacuation centers. Evacuees from previous volcanic eruptions usually suffered headache, fever, hypertension, acute gastroenteritis and respiratory tract infection, he said.

Duque said his agencies would also rent additional portable toilets for evacuees.

Taal, which sits in the center of a picturesque lake south of the capital, is under the second highest danger level, which meant "hazardous explosive eruption is possible within hours to days," said state seismology institute Phivolcs.

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One of the most active volcanoes in the Philippines, Taal has erupted more than 30 times in the past 5 centuries, most recently in 1977. An eruption in 1911 killed 1,500 people and one in 1754 lasted for a few months. With a report from Reuters