Typhoon Kalmaegi, which killed at least 114 people in the Philippines, is barrelling towards central Vietnam with increasing windspeeds.

Thousands of people who live in coastal communities have been asked to evacuate ahead of its arrival, which is expected to bring waves of up to 8m (26 ft), according to Vietnam's weather bureau.

Kalmaegi, one of the strongest typhoons this year, is likely to cause further devastation in a country which has already been battling record rains and deadly floods over the past week.

More than 50 flights have been cancelled or rescheduled, while six airports in the region have suspended operations.

Vietnam's Deputy Prime Minister Tran Hong Ha called Kalmaegi a very abnormal storm and urged local officials to treat it with urgency.

Earlier on Thursday, Philippines President Ferdinand Marcos Jr declared a state of calamity after the typhoon left a trail of deaths and devastation in his country.

The storm has flooded entire towns on Cebu, the region's most populous island, where 71 deaths were reported. Another 127 are missing and 82 injured, according to officials.

President Marcos Jr told reporters on Thursday that he made the decision because of the damage already caused by Typhoon Kalmaegi, and in anticipation of another storm Uwan, which is expected to hit the country over the weekend.

Almost 10 regions, around 10 to 12 regions, will be affected. So if that many areas are involved, with that kind of scope, then it's a national calamity, he told local media.

In the Philippines, a state of calamity is a condition involving mass casualty, major damage to property, and disruption to means of livelihoods and normal way of life for people in the affected areas.

Most of the deaths in the Philippines were due to drowning, reports said. The storm sent torrents of muddy water down hillsides and into towns and cities, with damage described as unprecedented by officials.

Residents returning to their destroyed homes are still reeling from the deadly floods earlier this week. Over 400,000 people have been displaced due to the disaster in Cebu.

"This is the worst flood I've ever experienced," said one volunteer rescuer. "Almost all the rivers here in Cebu overflowed."

As Kalmaegi heads to Vietnam, officials are preparing for more potential devastation, urging readiness against the incoming storm. Thailands is also on alert for flash floods and landslides due to the typhoon.