Three suicide bombers involved in an attack on Istanbul's main airport on Wednesday opened fire before blowing themselves up, according to initial findings, Turkish Prime Minister Binali Yildirim said.
Yildirim told reporters at the airport that there were likely to be foreigners among the 36 people killed, and that militant group IS may have been responsible.
"The signs point to Daesh but the investigation is ongoing," he said, Daesh is another name for IS.
The number of people wounded in the attack rose to 106, broadcaster NTV said, citing hospital sources.
