* Protester died in early hours in southern province
* Rallies held in Istanbul, Ankara to mark his death
* Protests diminished since July, but some unrest remains (Adds details from protests in other cities)
By Ece Toksabay
ISTANBUL, Sept 10 (Reuters) - Turkish police used teargas to disperse crowds in Istanbul and Ankara who were rallying against the death of a protester earlier in the day, witnesses said.
Police blocked protesters from reaching Istanbul's Taksim Square - the focus of recent anti-government protests.
Dozens of riot police backed by water cannon advanced down a main pedestrian and some fired teargas canisters and plastic pellets into side streets as protesters fled.
In the capital Ankara, more than 1,000 people gathered in the central square of Kizilay before police used water cannon and teargas to break up the crowd.
Broadcaster CNN Turk said protests also occurred in the southern province of Hatay at the funeral of Ahmet Atakan, 22, who died in the early hours of Tuesday at a demonstration against Prime Minister Tayyip Erdogan's handling of nationwide protests this summer.
The cause of Atakan's death was in dispute, with witnesses saying he suffered a blunt trauma to the head, while police said he fell from a rooftop.
Teargas in Istanbul forced UEFA match officials to temporarily halt play at an Under-21 match between Turkey and Sweden after gas affected players at the Recep Tayyip Erdogan Stadium near Taksim, CNN Turk reported.
Anti-government demonstrations have largely cooled since early July but there have been sporadic protests in Istanbul, Ankara and Hatay.
Tensions remain high in Hatay, a province of mixed ethnicities and religions that borders Syria, especially as the United States contemplates military strikes against President Bashar al-Assad over the suspected use of chemical weapons. (Additional reporting by Murad Sezer and Mert Ozkan; Writing by Daren Butler and Ayla Jean Yackley; Editing by Robin Pomeroy)