The secretary general of the Polisario Front, Mohamed Abdelaziz, has died at the age of 68.
Abdelaziz died on Tuesday afternoon after a long battle with illness, according to an official website of the separatist movement.
He died at a hospital in Algeria.
The movement ordered a 40-day mourning period, after which a new secretary-general will be chosen, the statement said.
Abdelaziz was born in 1948 in Smara. He was widely seen as one of the founders of the Polisario Front. He was the 3rd Secretary General of the Front, a position he held since 1976.
Experts say his death will have no major impact on the Western Sahara Conflict.