It's been three days since one of the worst storms ever to hit the Philippines' southern island of Mindanao left unprecedented death and destruction in its wake.

Rescue and relief efforts are underway, but hundreds are still missing following the heavy rains and flooding that struck on 17 December, and the death toll is rising. Benito Ramos, from the office of civil defence, put the official figure at 927 dead, including 579 in Cagayan de Oro and 279 in Iligan.

"So many bodies floated today and were retrieved, especially off Cagayan de Oro," said Ramos. "We've lost count of the missing."

The storm hit an area unaccustomed to such severe weather, and there was little or no government warning to evacuate. Many were swept away while they slept, while survivors frequently lost everything they owned.

Officials say 88,000 are now in evacuation centres. Supplies – including water, medicine and coffins – are in short supply. Bodies may have to be buried in mass graves to prevent the spread of infectious disease.

Esmar Sedurifa and her family survived purely because they had a two-storey home. When Sedurifa, 57, was woken by her son, the water was still quite low, leaving enough time for the family of seven to retreat upstairs.

"We moved to the second floor, but there was a brownout [reduced power]," says Sedurifa, who is dean of the Iligan Institute of Technology's college of education. "It was so dark we could not see. The sound of the water was so loud and [made us feel] very fearful. I could hear all the eerie voices calling for help and crying all around our home because all the other buildings have only one floor except ours."

The water rose from floor to ceiling in just half an hour. The strong current meant the only option was to climb through an unused air conditioning window and seek refuge on a neighbour's balcony, which provided safe shelter until the waters started to recede. Others in the community were not so lucky.

"We were praying that God should stop the rise of the water because it was coming up very, very fast," says Sedurifa. "People were continuously crying below; we used our phones as flashlights and said: 'Move on, move on'. We knew many were in the road and unable to hold on to each other; so many [were] taken by the current going into the sea."

Sedurifa's inability to help others haunts her. "At night I remember the sounds," she says. "People were shouting for help and we did not know how to help. [It was] so dark and we were not prepared … people [were] crying for rope and we could not provide them with rope. And the bodies – when the water receded, we saw two children alive clinging to a mango tree, but others were dead."

Venus Sabayle, 43, a housewife whose family lives by the sea in Iligan, believes only a miracle saved her. "We woke up to the sound of fishermen yelling to us to run away and save ourselves," she says.

With her infant grandchild, husband, and four other family members, Sabayle tried to escape. But when they opened their front door, the water was at shoulder height, and they found themselves trapped. "We stayed inside, but – when my husband heard the house start to creak and shake violently – we knew we had no choice but to try and leave."

Hoping to escape by sea, the family managed to find a boat. But while climbing into it, a log hit Sabayle's leg, knocking her into the water. "I was many metres under," she recalls. "I fought hard to make it to the surface. When I did, I saw a dog floating on a small surfboard. I could not believe it. I held on to it."

She then heard the cries of a little girl, looking for her mother. "I said: 'I am not your mother, but please keep hanging on to the log next to you'."

Hours later, when the two of them were rescued, Sabayle found all was not as it seemed. "I asked them to save also the dog," she says. "They told me there was no dog with me. I believe now that the Virgin Mary and San Roque sent the dog to rescue me."

Reunited with her family, Sabayle is now in an evacuation centre. "I never want to look at the water or sea again," she says, her voice trembling.

Nonetheless, survival has fuelled her strength to overcome any fear of the future.

"I have lost everything my family worked for – our house, our belongings – but I am grateful my family is still complete. I don't know how we will survive, but I have not lost hope. I look at those who have lost loved ones and I know I have experienced a miracle."