The National Assembly authorised President Idriss Deby's government to extend the exceptional powers, assumed on Feb. 14 to tighten security across the central African country after the assault.
The state of emergency gives the government wide search and arrest powers and also permits control of media reporting.
International and Chadian human rights groups have accused security forces in the Chad of arbitrarily arresting opponents of Deby on suspicion of aiding the opposition.
Ninety-two members of parliament voted to extend the state of emergency, with five abstentions and none against.
Several opposition members were absent, including former head of state Lol Mahamat Choua, under house arrest after being arrested as opposition forces retreated from N'Djamena on Feb. 3, and Ngarlegy Yorongar, who has been missing since then.
Yorongar's family say he was snatched by Deby's soldiers but the government says he was spotted last week at his home.
Another opposition politician, Ibni Oumar Mahamat Saleh is also missing after being seized from his home on Feb. 3, according to the anti-Deby coalition which he leads.
Following a request from French President Nicolas Sarkozy during a brief visit to Chad on Wednesday, Deby announced the setting up of an international commission to investigate the fate of Yorongar and Saleh.
Güncelleme Tarihi: 29 Şubat 2008, 15:26