The two men, aged 21 and 27, were among four people wounded near the southeastern village of Omerri when rocks were thrown at police during a demonstration to mark the 60th birthday of jailed PKK party founder Abdullah Ocalan, who was born in Omerri.

Police had responded using tear gas and water cannon.

The pair succumbed to their injuries after being transferred to a hospital in Sanliurfa, 110 kilometres (70 miles) away.

Fresh unrest broke out in the vicinity of the hospital, with a police officer also injured during the latest fighting.

Ocalan led the PKK's bloody campaign for self-rule in the southeast from 1984 until his arrest in February 1999 in Kenya.

Four months later, a Turkish court condemned him to death for treason, but the sentence was commuted to life in 2002 after Ankara abolished capital punishment as part of reforms to align with European Union norms.

The PKK is listed as a terrorist organisation by Ankara and much of the international community. For many Kurds, however, he remains a national hero.