The West African nation of Niger is observing three days of national mourning following the death of former President Mamadou Tandja at the age of 82.   The government said Tuesday Tandja died in the capital, Niamey, but no cause of death was given.  Tandja was twice elected president of Niger starting 1999 to 2010 before he was overthrown in a coup for attempting to change the constitution to hold onto power.  Tandja’s ouster paved the way for Issoufou Mahamadou to become president in the 2011 election. Tandja’s death came just over a month before Niger’s presidential election. 
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