MAIDUGURI, Nigeria, Feb. 1 (UPI) -- Boko Haram's attempt on Sunday to capture the city of Maiduguri has been repelled by the Nigerian army.
This is the third time in a week that Boko Haram assaulted Maiduguri, Nigeria's largest city in the northeast.
The attack is the first confirmed to use heavy mortars in the conflict between Boko Haram and the Nigerian army.
Local hunters and vigilantes confronted Boko Haram when they first arrived to the city and the Nigerian army followed soon after. The attack began early in the morning and Boko Haram was driven out by noon.
A Nigerian Defense Ministry spokesman said the attack was "contained" and the Islamic militants suffered a high death toll.
Boko Haram began its ongoing assault on Maiduguri on Jan. 25, but the Nigerian army has continued to repel the terrorist rebel organization.
Maiduguri is seen as a key, strategic city.
"Maiduguri is the capital of Borno state and is the metropole of northeastern Nigeria," the Council on Foreign Relations said. "It has become known as the city of Boko Haram's origin, and the venue where the movement's leader, Mohammed Yussuf, established his community and was eventually murdered by the police."
Maiduguri has an estimated population of 1.2 million.
Boko Haram was designated as a foreign terrorist organization by the U.S. State Department in 2013. The militant Islamic group seeks to establish an Islamic state in Nigeria and has ruthlessly targeted civilians.