Havana, Cuba (CNN) A crowd of Cubans stood around the mangled bus, some offering assistance, others recording the tragic scene with their cell phones.

On the ground lay two prone women, their faces obscured by blood-matted hair, as seen in video of the incident that was obtained by CNN. The roof of the bus they were traveling in was ripped open, and windows were shattered as if a bomb had gone off.

"She's already dead," cried a passerby as a good Samaritan tried to take the pulse of one of the women.

All around the bus lay huge chunks of cement; pieces of a nearby building that had collapsed under the brunt of Hurricane Irma.

Long before Irma, derrumbes -- as Cubans call building collapses -- were a common event. Ornate colonial balconies, facades, sometimes even whole buildings, give way after decades of neglect and come crashing down with little to no warning.

Havana residents joke that their's might be the only city in the world where it's safer to walk in the middle of the road than on the sidewalks, in case the heavy stone edifices come crashing down.

Of the 10 deaths that Cuba has blamed on Hurricane Irma, at least five were the result of building collapses.

Irma hit Cuba as a monster Category 5 storm and laid waste to hundreds of buildings in the storm's path. But Cuban officials worry that many more thousands of structures could be weakened and eventually fall.

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According to the state-run newspaper Granma, just in Havana, over 300 miles from the where Irma made landfall, at least 157 homes were destroyed and an additional 4,288 homes were weakened by Irma.

In the weeks to come, the damaged buildings could shift and suddenly disintegrate.

Litza Peñalver Sierra on Wednesday, amid the rubble of an apartment where two brothers died after Hurricane Irma caused their ceiling to cave in on them.

"The combination between the water and the sun create expansion and contraction and that creates structural problems in the building which you cannot predict," said Cuban architect Yoandy Rizo Fiallo. "You don't expect anything and then the building falls."

Cuba has been in an economic crisis since the fall of the Soviet Union and suffered under more than five decades of US economic sanctions. The Cuban government maintains the exclusive right to import items to the island and at state-run hardware stores many building materials are overpriced, shoddy or simply nonexistent.

The lack of new construction has led Cubans to subdivide their homes, putting more strain on already creaking buildings.

Cuban President Raul Castro vowed the country would bounce back from the ravages inflicted by Irma, the strongest hurricane to hit the island in over 80 years.

"One principle remains immovable: the Revolution will leave no one unprotected," Castro said in a statement addressed to the Cuban people. "And measures are already being adopted to ensure that no Cuban family is left to their fate."

Photos: Hurricane Irma tears through Caribbean Carmelo Mota, a builder, searches for tools in his destroyed home in Charlotte Amalie, US Virgin Islands, on Monday, September 18. Hurricane Irma devastated the US territory and other Caribbean islands in the region, leaving them exposed to new storms brewing in the Atlantic. Hide Caption 1 of 55 Photos: Hurricane Irma tears through Caribbean An aerial photo shows the devastation in Road Town, the capital of Tortola, the largest and most populated of the British Virgin Islands, on Wednesday, September 13. Hide Caption 2 of 55 Photos: Hurricane Irma tears through Caribbean UK Foreign Secretary Boris Johnson talks to a resident of Anguilla during a visit on September 13. Hide Caption 3 of 55 Photos: Hurricane Irma tears through Caribbean People collect food that was delivered by emergency workers in the Sandy Ground area of Marigot, St. Martin, on Tuesday, September 12. Hide Caption 4 of 55 Photos: Hurricane Irma tears through Caribbean Buildings are destroyed in St. Martin on September 12. Hide Caption 5 of 55 Photos: Hurricane Irma tears through Caribbean French President Emmanuel Macron shakes hands with St. Martin residents during a visit to the island on September 12. Hide Caption 6 of 55 Photos: Hurricane Irma tears through Caribbean French soldiers patrol St. Martin on September 12. Hide Caption 7 of 55 Photos: Hurricane Irma tears through Caribbean A person works to clean up a street September 12 after Hurricane Irma flooded parts of Havana, Cuba. Hide Caption 8 of 55 Photos: Hurricane Irma tears through Caribbean A man makes repairs in Havana on September 12. Hide Caption 9 of 55 Photos: Hurricane Irma tears through Caribbean This Marigot church was among the buildings destroyed in the storm. Hide Caption 10 of 55 Photos: Hurricane Irma tears through Caribbean Cubans affected by Hurricane Irma line up to collect drinking water in Isabela de Sagua, Cuba, on Monday, September 11. Hide Caption 11 of 55 Photos: Hurricane Irma tears through Caribbean Dutch King Willem-Alexander, front right, tours damage in St. Maarten on September 11. Hide Caption 12 of 55 Photos: Hurricane Irma tears through Caribbean A palm tree sticks out of a pool on the French side of St. Martin on September 11. Hide Caption 13 of 55 Photos: Hurricane Irma tears through Caribbean A woman stands next to her water-logged belongings that had been laid out to dry in front of her home in Isabela de Sagua on September 11. Hide Caption 14 of 55 Photos: Hurricane Irma tears through Caribbean People line up for supplies in St. Martin on September 11. Hide Caption 15 of 55 Photos: Hurricane Irma tears through Caribbean The skeleton of a boat drifts in St. Martin's Simpson Bay on September 11. Hide Caption 16 of 55 Photos: Hurricane Irma tears through Caribbean People salvage material from the remains of a house in Isabela de Sagua on September 11. Hide Caption 17 of 55 Photos: Hurricane Irma tears through Caribbean Members of the British Army provide support on Tortola, one of the British Virgin Islands. Hide Caption 18 of 55 Photos: Hurricane Irma tears through Caribbean A woman carries a dog at an airport checkpoint in St. Martin on September 11. Hide Caption 19 of 55 Photos: Hurricane Irma tears through Caribbean People wade through a flooded street as a wave crashes in Havana on Sunday, September 10. Hide Caption 20 of 55 Photos: Hurricane Irma tears through Caribbean Two men search through the rubble of their St. Martin restaurant on September 10. Hide Caption 21 of 55 Photos: Hurricane Irma tears through Caribbean People make their way through debris in the Cojimar neighborhood of Havana on September 10. Hide Caption 22 of 55 Photos: Hurricane Irma tears through Caribbean People board a plane leaving St. Martin on September 10. Hide Caption 23 of 55 Photos: Hurricane Irma tears through Caribbean A man wades through a flooded street in Havana on September 10. Hide Caption 24 of 55 Photos: Hurricane Irma tears through Caribbean An overview of Havana shows flooded streets on Saturday, September 9. Hide Caption 25 of 55 Photos: Hurricane Irma tears through Caribbean A woman surveys flooding in Havana on September 9. Hide Caption 26 of 55 Photos: Hurricane Irma tears through Caribbean A boat rests in a cemetery after Irma tore through Marigot, St. Martin. Hide Caption 27 of 55 Photos: Hurricane Irma tears through Caribbean Residents return home after Irma passed through Caibarien, Cuba, on September 9. Hide Caption 28 of 55 Photos: Hurricane Irma tears through Caribbean A man walks in Caibarien on September 9. Hide Caption 29 of 55 Photos: Hurricane Irma tears through Caribbean A man carries a child through a flooded street in Fort-Liberte, Haiti, on Friday, September 8. Hide Caption 30 of 55 Photos: Hurricane Irma tears through Caribbean A man walks on a St. Martin street covered in debris on September 8. Hide Caption 31 of 55 Photos: Hurricane Irma tears through Caribbean A damaged home is tilted onto its side on the Puerto Rican island of Culebra on Thursday, September 7. Hide Caption 32 of 55 Photos: Hurricane Irma tears through Caribbean A home is surrounded by debris in Nagua, Dominican Republic, on September 7. Hide Caption 33 of 55 Photos: Hurricane Irma tears through Caribbean Irma damage is seen in St. Martin's Orient Bay on September 7. Hide Caption 34 of 55 Photos: Hurricane Irma tears through Caribbean Employees from an electrical company work to clear a fallen tree in Sanchez, Dominican Republic. Hide Caption 35 of 55 Photos: Hurricane Irma tears through Caribbean A woman makes her way through debris in Fajardo, Puerto Rico, on September 7. Hide Caption 36 of 55 Photos: Hurricane Irma tears through Caribbean In this image made from video, damaged houses are seen in St. Thomas on September 7. Hide Caption 37 of 55 Photos: Hurricane Irma tears through Caribbean The storm left widespread destruction on the island of Barbuda on September 7. Hide Caption 38 of 55 Photos: Hurricane Irma tears through Caribbean A flattened home is seen in Nagua, Dominican Republic, on September 7. Hide Caption 39 of 55 Photos: Hurricane Irma tears through Caribbean Nagua residents ride through an area affected by the storm on September 7. Hide Caption 40 of 55 Photos: Hurricane Irma tears through Caribbean Trash and debris is washed ashore in Cap-Haitien, Haiti, on September 7. Hide Caption 41 of 55 Photos: Hurricane Irma tears through Caribbean People walk through damage in Marigot, St. Martin, on September 7. Hide Caption 42 of 55 Photos: Hurricane Irma tears through Caribbean People survey damage in Marigot on September 7. Hide Caption 43 of 55 Photos: Hurricane Irma tears through Caribbean Bluebeard's Castle, a resort in St. Thomas, was hit hard by Irma. St. Thomas resident David Velez sent this photo to CNN on September 7. Hide Caption 44 of 55 Photos: Hurricane Irma tears through Caribbean Irma ruined these vehicles in St. Thomas. Hide Caption 45 of 55 Photos: Hurricane Irma tears through Caribbean Waves smash into St. Martin on Wednesday, September 6. Hide Caption 46 of 55 Photos: Hurricane Irma tears through Caribbean A man looks at a vehicle turned upside down in the British territory of Anguilla. Hide Caption 47 of 55 Photos: Hurricane Irma tears through Caribbean An aerial view of St. Martin on September 6. Hide Caption 48 of 55 Photos: Hurricane Irma tears through Caribbean Damaged cars are seen on a St. Martin beach on September 6. Hide Caption 49 of 55 Photos: Hurricane Irma tears through Caribbean A boat is washed onto shore in St. Martin. Hide Caption 50 of 55 Photos: Hurricane Irma tears through Caribbean Cars are piled up in Marigot on September 6. Hide Caption 51 of 55 Photos: Hurricane Irma tears through Caribbean A man walks past damaged buildings in St. Martin on September 6. Hide Caption 52 of 55 Photos: Hurricane Irma tears through Caribbean A car is flipped onto its side in Marigot. Hide Caption 53 of 55 Photos: Hurricane Irma tears through Caribbean Broken palm trees are scattered on a Marigot beach on September 6. Hide Caption 54 of 55 Photos: Hurricane Irma tears through Caribbean Irma floods a beach in Marigot on September 6. Hide Caption 55 of 55

But many Cubans are waiting for that help to arrive.

A building collapse in Havana killed two brothers who lived alongside Litza Sierra Peñalver and her family.

Their apartment building in Centro Habana was already at risk of collapse when the roof over the brothers' apartment gave way, killing them instantly, Peñalver said.

Peñalver said she left the building last year, after living there for over 20 years, when her ceiling also came crashing down. Her son, sister and nephews stayed behind in another apartment, she said.

"Don't live here, danger of building collapse," read a sign scrawled on the wall of the second floor where the men died. Residents of the building hang dried marabu grass over entrances to their apartments and nail dead cockroaches to their doors, Santería traditions to ward off misfortune.

"If you live here, you pray a lot," Peñalver said.

Residents showed cellphone video of Cuban civil defense officials carrying the men's bodies out of the building in what appeared to be large black trash bags.

"It's painful because it could have been avoided if the authorities had taken measures," she said.

Now the back half of the building is open to the elements. Water pours in from holes in the roof and the floor on the second story tilts at an angle.

Cuban government officials contacted by CNN about the case of Peñalver's family and the other residents of the building said they had warned them about the approaching storm and that they were trying to get them to leave the building for their own safety, even if that meant going to a shelter while the government tried to find them permanent housing.

"What happens is they don't accept going to a shelter, they want a permanent solution. As everyone knows when a hurricane comes it's devastating and leaves complicated economic situations," said Eider Herrera Morales, a local government official for the neighborhood where Peñalver's family lives.

But Peñalver rejected having her family going to a temporary shelter, saying they would be stranded there for years until housing was provided for them.

"They were elected to help the people, if not them, who?" she said of the local Communist Party officials, who she said had provided them with scant assistance. "We don't have an answer. They just say 'wait.' "

The rest of the building could go at any time,

"We don't go to sleep," Peñalver said. "Because we are afraid we won't wake up."