Turkish Kurds and refugees from fighting in Syria have clashed with Turkish security forces on the border between the two countries.
Troops used tear gas and water cannon to disperse protesters angry at the situation in Syria, where IS militants are closing in on the town of Kobane.
Meanwhile unconfirmed reports say at least 35 militants were killed in US-led air strikes over northern Syria.
They come amid a Turkish-US row over alleged support for Syrian militants.
On Friday US Vice-President Joe Biden criticised Turkey and US allies in the Arab world for supporting Sunni militant groups such as Islamic State, prompting a sharp response from Turkish President Recep Tayyip Erdogan.
"If Mr Biden used such language, that would make him a man of the past for me," he told a news conference in Istanbul.
"No-one can accuse Turkey of having supported any terrorist organisation in Syria, including IS."