The camels were found in the same barn, and had been in contact with two humans who fully recovered from the Middle East Respiratory Syndrome, said the country's Supreme Council of Health.

It was the second reported case of animals infected with MERS after Saudi Arabia announced a camel had tested positive for the virus this month.

The World Health Organization says it has been informed of 160 laboratory-confirmed cases of infection worldwide since September last year, including 68 deaths.

Saudi Arabia is the worst affected country, accounting for 55 deaths.

Experts are struggling to understand the MERS virus, for which there is no vaccine.

It is considered a deadlier but less-transmissible cousin of the SARS virus that erupted in Asia in 2003 and infected 8,273 people, nine per cent of whom died.

In August, researchers pointed to Arabian camels as possible hosts of the virus, which has hit hardest in the desert kingdom.

Like SARS, MERS appears to cause a lung infection, with patients suffering from a temperature, cough and breathing difficulty.

But it differs in that it also causes rapid kidney failure and the extremely high death rate has caused serious concern.

SHI/SHI