The protesters were demonstrating against Turkey's recent air strikes on Kurdish rebel bases in Iraq.

Yildirim Ayhan, a provincial assembly member of the southeastern province of Van, died after the tear gas cartridge hit him in the chest, as the military police attempted to disperse a crowd of protesters in the town of Cukurca, witnesses and security sources said.

"The superiors of the soldiers opposite to us suddenly ordered them to intervene. They started to fire tear gas. One of the cartridges hit Ayhan and we saw him slumping," a witness told AFP.

"He was bleeding from his chest," another witness said.

Security sources confirmed Ayhan had been struck by a gas cannister, but said an autopsy would determine the cause of death.

Pro-Kurdish media published photographs of Ayhan lying on the ground with a bleeding chest wound.

Thousands of people from 16 different provinces started to march on Saturday towards the Turkey-Iraq border to demonstrate against the army's bombing raids on bases of the Kurdistan Workers' Party (PKK) in northern Iraq.

Protesters, calling themselves "human shields" against the strikes, included parliamentarians from the pro-Kurdish Peace and Democracy Party (BDP). Ayhan was also a member of the BDP.

The Turkish military launched several waves of bomb attacks this month against PKK targets in Iraq after a deadly attack by the rebel group against a military unit in Cukurca, in southeast Turkey, that killed nine security personnel.

The PKK, listed as a terrorist group by Ankara and much of the international community, took up arms in the Kurdish-majority southeast in 1984, sparking a conflict that has claimed about 45,000 lives.