Chad is located in central Africa. The Chad Republic covers an area of 9,545 square kilometers and has a population of around 8 million people. The capital and largest city is N'Djamena. In 2009, Chadian President Idriss Déby accused Sudan of plotting his overthrow and invading the country from its southern border. In early 2011, Chad's longtime ruler, Ali Mahdi Saleh, was overthrown by a military coup led by General Idriss Déby. Chadian citizens have the right to vote in national elections that are held every five years.