A group of experts from the World Health Organisation has gone to eastern Turkey where three children have died after being infected with bird flu.
There are now four confirmed cases of the deadly H5N1 strain of the disease in a town close to the Iranian border.
Reports say the virus has not been passed from human to human, but the investigation will focus on the source of the outbreak.
And in the capital, Ankara, it is reported that three more people, two children and an adult, have tested positive for the virus.
The two children are from a town 100km northwest of Ankara.
