Turkey's state-run news agency says a fire at a refugee camp near the border with Syria has killed three Syrian children and wounded six other people.

Anadolu Agency says the cause of Tuesday's fire in the camp housing some 20,000 refugees is under investigation. The camp is located near the town of Derik, in Mardin province.

The private Dogan news agency says the children were aged between 3 and 8.

It said a child was also killed in the camp last week in a fire that destroyed 21 tents.

Some 2.7 million refugees from Syria have found refuge in Turkey, making it the country with the largest refugee population in the world.