Published: Jan 11, 2012 4:36 PM EST

TUNIS, Tunisia (AP) - A local official in the Tunisian city of Sfax says a middle-aged woman has died after setting herself on fire - the fourth case of self-immolation in the last week in the North African nation.
    
Malek Mihoub said Wednesday the woman had a history of mental illness.
    
Her suicide followed that of a father of four in Gafsa who set himself on fire Thursday and died five days later. The two others, in the towns of Bizerte and Siliana, survived.
    
These acts of desperation, often protesting the inability to find work, come as the Jan. 14 anniversary nears of the 2011 overthrow of Tunisia's dictatorship. That uprising began after a young vegetable seller set himself on fire and died to protest government injustice.

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