An eight-year-old Cambodian girl has died of bird flu, the 51st known victim of the deadly virus since it swept across Asia at the end of 2003.

Health officials said Sunday the girl was from the same province as the two other Cambodian victims, Kampot, on the border with Vietnam, which has been hit worst by the H5N1 virus with 36 victims.

Twelve Thais have also died of the virus, which the World Health Organization says has the potential to mutate into a form that could pass easily between humans and cause a pandemic in which millions of people could die.

The girl died in a Phnom Penh hospital Thursday night and laboratory tests confirmed she had bird flu the following day, the health officials said.

She probably caught the disease directly from infected poultry, like most of the other victims, they said.

Tens of millions of fowl have died of bird flu or been slaughtered in a so far vain attempt to kill off the virus, which the WHO says is now endemic in parts of southeast Asia.