Electoral body says President Deby’s party secured 124 of 188 National Assembly seats in vote boycotted by opposition.
Assault on N’Djamena comes amid visit by China FM, withdrawal of French troops, and instability caused by armed groups.
At least 19 people have been killed in Chad where security forces said they had prevented an attack by armed fighters.
The attack came just hours after China’s Foreign Minister Wang Yi met with government officials in the capital N’Djamena