Idriss Déby had reelected for another term as president of the Central African country by 79.3% on Monday.
He was reportedly visiting frontline troops fighting to stop a rebel advance on the capital, N’Djamena.
The rebel group known as the Front for Change and Concord in Chad is believed to have armed and trained in neighboring Libya before crossing into the north of the country.
The Army said it had managed to beat back a column of insurgents who were advancing on the capital.