A gun and bomb attack on Istanbul's Ataturk airport has killed 41 people, at least 13 of them foreigners, and injured more than 230, officials say.
Three attackers arrived in a taxi and began firing at the terminal entrance late on Tuesday. They blew themselves up after police fired back.
PM Binali Yildirim said early signs pointed to so-called Islamic State but no-one has so far admitted the attack.
Recent bombings have been linked to either IS or Kurdish separatists.
Tuesday's attack looked like a major co-ordinated assault, says the BBC's Mark Lowen.
Ataturk airport has long been seen as a vulnerable target, our Turkey correspondent adds, reporting from a plane stuck on the tarmac in Istanbul.
There are X-ray scanners at the entrance to the terminal but security checks for cars are limited.
Pictures from the airport terminal showed bodies covered in sheets, with glass and abandoned luggage littering the building.
Turkish President Recep Tayyip Erdogan said the attack should serve as a turning point in the global fight against militant groups.
"The bombs that exploded in Istanbul today could have gone off at any airport in any city around the world," he said.
The US called the attack "heinous", saying America remained "steadfast in our support for Turkey".
German Interior Minister Thomas de Maiziere called the attacks "cowardly and brutal".
'Dressed in black'
Istanbul's governor confirmed 41 people had died and 239 were injured in the attack. At least 13 of those killed were of foreign or dual nationality. Some 109 of those hurt have now been discharged from hospital.
One Iranian and one Ukrainian were confirmed dead.
Reports of the attack vary but it appears the attackers opened fire at the entrance where the X-ray machines are positioned, sparking an exchange with police. At least two ran into the building.
Footage on social media shows one moving through the building as people around him flee. He is shot by police and remains on the ground for about 20 seconds before blowing himself up. All three attackers were killed.