The death toll from cyclone Shaheen has risen to 13 while other fishermen remain missing as the storm moved further inland into Oman and weakened.
Authorities in Oman said they found the body of a man who disappeared when floodwaters swept him away from his vehicle.
On Sunday as the storm made landfall, they said a child drowned and two foreigners from Asia died in a landslide.
The country’s National Committee for Emergency Management announced seven additional deaths from the storm, without elaborating.
In Iran, state television said rescuers found the body of two of five fishermen who went missing off Pasabandar, a fishing village near the Islamic Republic’s border with Pakistan.
Earlier on Sunday, Iranian deputy parliament speaker Ali Nikzad said he feared as many as six fishermen had been killed because of the cyclone.
More than 120 people in Iran’s Sistan and Baluchestan province were taken hospital on Sunday after a dust storm spun up by the cyclone caused them to suffer from eye, heart and lung problems, said Abbasali Arjmandi, the governor of the city of Zabol.
India’s Meteorological Department, the top forecasters for cyclones that sweep across the Indian Ocean, said winds from Shaheen now gust up to 90km/h and would continue to weaken.
It predicted the storm would weaken into a tropical depression in the coming hours. Shaheen made landfall with winds reaching up to 150km/h.
Omani state television broadcast images of flooded roads and valleys as the storm churned deeper into the sultanate, its outer edges reaching the neighbouring United Arab Emirates.
The Emirates, home to Abu Dhabi and Dubai, had issued warnings to residents that the storm was coming.
Winds had picked up from Sunday, sweeping across the grounds of Dubai’s newly opened Expo 2020.
A cyclone is the same as a hurricane or a typhoon. Hurricanes are spawned east of the international date line, and typhoons develop west of the line. They are known as cyclones in the Indian Ocean and Australia. – PA