A powerful cyclone has hit the coastlines of Bangladesh and Myanmar after intensifying into the equivalent of a category-five storm.

Cyclone Mocha did not make landfall at the world’s largest refugee camp in Cox’s Bazar, as earlier feared, but still destroyed hundreds of makeshift shelters in the camp.

At least five people have been reported dead in Myanmar. No casualties have been reported in Bangladesh so far.

By late Sunday, the storm had largely passed. Bangladesh’s disaster official Kamrul Hasan said the cyclone caused “no major damage” in his country, but landslides and floods are still hitting the area.

Myanmar appears to have borne more direct impact, with the storm crashing through houses and cutting power lines in the western Rakhine state. Camps for displaced Rohingya in Rakhine state were also ripped apart.

Local media reported that a 14-year-old boy was killed by a falling tree in the state, while there were reports of damaged and collapsed buildings across the country. Electricity and wireless connections were disrupted across much of the state capital Sittwe, and footage online shows a telecom tower brought down by strong winds as the cyclone approached.

Videos shared on social media also showed roofs being blown off houses and billboards flying off buildings in Yangon amid teeming rain. Images from the city of Mrauk U showed palm trees bending in the wind, metal roofing sheets being swept into the street and a few people still hurrying to take cover in storm shelters.

The Myanmar Red Cross Society said it was “preparing for a major emergency response”. Authorities in Bangladesh had evacuated 750,000 people ahead of the storm. The streets of Cox’s Bazar emptied as the cyclone intensified – the skies darkened, the winds picked up pace and the rains pounded down.

Hundreds of people crammed into a school which had been turned into a temporary cyclone shelter. Mothers with babies, young children, the elderly and the frail packed into any available space in the classrooms, sleeping on desks and sitting under them.

As many arrived at the shelter in rickshaws and on foot, they brought their livestock – cattle, chickens, goats – as well as mats to sleep on. They had come from fishing and coastal villages up to two hours away, making a difficult choice.

Authorities said that more than 1,300 shelters were damaged by the wind, as were 16 mosques and learning centres. Trees had fallen in the camps, while two landslides also caused some damage.

Mizanur Rahman, from the Refugee Relief and Repatriation Commissioner, said that as far as he was aware, there were no casualties in the camps as a result of the cyclone.

Forecasters warned Cyclone Mocha could be the most powerful storm seen in Bangladesh in nearly two decades.

The Bangladeshi meteorological department office said the maximum sustained wind speed within 75km (45 miles) of the centre of the cyclone was about 195km/h (120mph), with gusts and squalls of 215km/h.

In preparation for the storm’s arrival, nearby airports had been shut, fishermen were ordered to suspend their work and 1,500 shelters set up as people from vulnerable areas were moved to safer spots.

In 2008, Cyclone Nargis tore through the southern coastal regions of Myanmar, killing almost 140,000 people and severely affecting millions. Most of those who died were killed by a 3.5 metre wall of water that hit the low-lying Irrawaddy Delta.