On Saturday, despite efforts by the authorities, Oman was still coping with a serious lack of potable water.
In Muscat, Oman's capital, authorities struggled to reinstate electricity and water supplied.
The Royal Oman Police were reported in the Oman Tribune as issuing a "warning to opportunists who might want to exploit the present circumstances to their advantage".
Authorities have set up water distribution points in a number of areas around the city in an attempt to deal with the crisis.
According to Omani news sources, the cyclone damaged the two power and desalination plants that supply Muscat with potable water and the plants have only been partially re-started.
Al Jazeera has also received reports that a landslide in Muscat has caused closure of some roads in the capital.
Cyclone Gonu swept through Oman on Wednesday, forcing thousands from their homes, cutting off electricity and damaging infrastructure.
In Iran, an official in charge of natural disasters was quoted by the semi-official Mehr news agency as saying: "So far 12 people in Sistan-Baluchistan and Hormuzgan have been killed and 9 have been injured due to floods".
The report gave no further details of the deaths.
Iran's Fars news agency, meanwhile, quoted another official as saying that a total of "40,000 villagers are trapped by water in Hormozgan province".
Helicopters have been dispatched to the affected areas, the official said, while Iran's Revolutionary Guards Air Force said on Friday it had delivered 40 tonnes of food to the port city of Chabahar in Sistan-Baluchestan province.
An Iranian Interior Ministry official told Mehr the full extent of damage caused by the hurricane had yet to be assessed due to difficulties communicating with the worst-hit areas.