Two more suicide bombers detonated their devices at the gates to a nearby refugee camp, wounding many people, an emergency services official said. They detonated their explosives nearly simultaneously, Lawan Kalli said.
But correspondents say that the army is failing to stop the attacks, and people have continued to flee their homes in Borno State and poured into camps.
A local medical source said that following the blasts a "huge number" of people were admitted to the Maiduguri hospital.
In recent weeks, a number of bomb attacks by suspected members of Boko Haram have taken place in the capital of Borno state and its environs.
Ibrahim Attahiru, theatre commander major general on Tuesday, August 15, said the outfit is made up of specially selected forces with mixed equipment to succeed in the fight against Boko Haram terrorists.
Boko Haram has waged an eight-year-war to create an Islamic state in northeast Nigeria. "People were trying to close their shops when two other female bombers triggered their explosives, causing most of the casualties", he added.More news: China protests USA ship near South China Sea island
The Nigerian military has captured several areas of Boko Haram surveillance previous year.
But the radical group has struck back with renewed zeal since June.
The group has, however, resorted to sporadic shooting attacks and bombings in the northeast of the African country, spreading panic among local residents.
The attack prompted Vice President Yemi Osinbajo, who is standing in for President Muhammadu Buhari while he is on indefinite sick leave, to ask the military to step up its response.
Abubakar Shekau is the current leader of the militant Islamist group Boko Haram, he was deputy to founder Mohammed Yusuf, who was killed by police in 2009 while in custody.