A bomb attack on an outdoor wedding party in south-eastern Turkey that killed 50 people and wounded dozens of others was the work of IS, the country's president said.
Officials said Saturday's attack in Gaziantep, near Syria's border, seemed to be a suicide bombing. It appeared to be just an ordinary wedding and it was not clear why it was targeted.
The remains of a suicide vest have been recovered at the site, according to the state-run Anadolu Agency, citing a statement by the chief public prosecutor's office.
President Recep Tayyip Erdogan issued a statement early Sunday denouncing the "heinous" bombing and saying that IS was "the most likely perpetrator of the Gaziantep attack".
The initial death toll was 30 killed and 94 wounded. Later, the Gaziantep governor's office raised the toll to 50, without giving a number of wounded, according to Anadolu. It is the deadliest extremist attack of 2016.
In June, suspected IS militants attacked Istanbul's main airport with guns and bombs, killing 44 people. A dual suicide bombing blamed on IS at a peace rally in Turkey's capital, Ankara, in October killed 103 victims.
The attack comes as the country is still reeling from last month's failed coup attempt, which the government has blamed on US-based Muslim cleric Fethullah Gulen and his followers. Gulen denies any involvement.
Erdogan said there was "absolutely no difference" between IS, Kurdish rebels and Gulen's movement, calling them terrorist groups.
"These bloodthirsty organisations and the powers behind them have neither the will nor power to silence the calls to prayer, lower the flag, divide our motherland and break up our nation," he added.
Turkish authorities issued a media blackout on coverage of the attack until the investigation is completed.