Bahrain's civil aviation authority suspended all flights arriving from Dubai and Sharjah for 48 hours early on Tuesday.
The move appeared to be made to protect the kingdom against the further spread of coronavirus, after the country recorded its first two confirmed cases on Monday and a further six on Tuesday.
One Bahraini citizen, a woman, showed symptoms after arriving on a flight from Iran and was transferred to the Ebrahim Khalil Kanoo Medical Centre for immediate testing, treatment and isolation, the country's Ministry of Health said.
A second patient, a school bus driver, arrived from Iran, via Dubai, on February 21. They were well at the time, but developed symptoms a "few days later" according to the Bahrain News Agency.
Six further cases - two Bahrainis and four Saudis - were diagnosed on arrival in Manama, Bahrain's Ministry of Health said on Tuesday.
In a tweet, ministry officials said the passengers arrived from Iran via Dubai, "confirming a total of 8 registered cases in the kingdom".
Speaking about the bus driver, the ministry said he attended work on Sunday, dropping off children at two schools and one kindergarten. The families of all children who took the bus have been tested as a precaution, as have the passengers on the man's flight to Bahrain.
"The ministry underlined the [two] schools and kindergarten will be closed for two weeks, in co-operation with the Ministry of Education, as a precautionary measure," the news agency said.
Bahrain's Civil Aviation Affairs urged "citizens and residents of Bahrain who are currently in areas affected by the coronavirus and who were planning to return to the kingdom of Bahrain" to call a dedicated telephone number.
"The CAA affirms that it is co-operating with all authorities to take the necessary measures in light of Covid-19. All arrivals to Bahrain International Airport suspected of infection will be tested and, if found to be suffering from the condition, are immediately transferred to designated centres for isolation and treatment," a statement carried by the news agency said.
The flight ban affects at least 15 flights a day to Bahrain from Dubai International Airport.
"Due to the temporary suspension of air services between Dubai and Bahrain, the following Emirates flights have been cancelled on February 25 and 26: EK837/838: Dubai – Bahrain - Dubai, EK839/840: Dubai – Bahrain - Dubai, EK833/834: Dubai – Bahrain - Dubai, EK835/836: Dubai – Bahrain - Dubaia," a spokeswoman for Emirates said.
"Passengers are advised to check emirates.com for further updates on affected flights and the latest flight schedule.
"We’re monitoring the situation closely and will update our customers as the situation develops. Affected customers are requested to contact their travel agent, or Emirates office for rebooking options or refunds."
Bahrain was one of several countries across the region to announce their first cases of the virus on Monday.
Oman, Kuwait, Iraq and Afghanistan also announced their first cases of Covid-19, most of which had affected people who had visited Iran, where the virus is said to be spreading rapidly.
According to official figures, Iran has 61 confirmed cases of the virus and 12 deaths, although a MP for Qom, the worst-affected city in Iran, said the death toll stood at 50 in his city alone.
Ahmad Amirabadi Farahani was quoted by the semi-official ILNA news agency as saying the 50 deaths dated as far back as February 13. However, the first reported cases and deaths in Iran were only released on February 19.
The Iranian government has denied attempting to cover up the full extent of the outbreak.
"I categorically deny this information," the country's deputy health minister, Iraj Harirchi, said. "This is not the time for political confrontations. The coronavirus is a national problem," he added.
There have been 13 cases of Covid-19 in the UAE, the latest of which were announced in two Iranian tourists on Saturday. The man was in an "unstable" condition and in intensive care on Saturday, officials from the Ministry of Health and Prevention said.
The first four cases occurred in a Chinese family on holiday in late January. The mother, father, girl, 9, and grandmother from Wuhan, China, the centre of the outbreak, were confirmed to have the virus after visiting a local health clinic a week into their trip.
They arrived in the UAE on January 16 and first sought treatment on January 23 after the grandmother developed flu-like symptoms. All four subsequently developed the disease.
Further cases were diagnosed in three Chinese citizens, two Filipinos, one Indian citizen and a Bangladeshi, as well as the two Iranians. Three of those infected have subsequently recovered.
On Monday, the Ministry of Foreign Affairs and International Co-operation announced Emiratis were banned from travelling to Iran and Thailand after an outbreak of Covid-19.
The ministry said the ban was put in place "to ensure the health and safety of UAE citizens" and to stop the spread of coronavirus.
It called on Emiratis to contact the UAE embassies in Iran or Thailand, or the ministry's call centre on 80044444 for more information.
Covid-19 is one of seven known coronaviruses that can infect people – four of which result in symptoms no more serious than the common cold.
The exceptions include Sars, which has a fatality rate of 14 to 15 per cent; Mers, which kills about 35 per cent of people it infects; and Covid-19. The mortality rate has yet to be confirmed for the latest virus, but of the 80,150 confirmed cases worldwide, 27,633 people have so far recovered, and 2,701 have died. Almost 50,000 people remain infected.
Like Sars and Mers, Covid-19 can lead to pneumonia.