At least 10 people were killed and 39 others injured when four suicide bombers blew themselves up in the city of Maiduguri, northeast Nigeria, the military said on Friday.

"So far it has been confirmed that 14 people have lost their lives, including the suicide bombers, while 39 people were wounded," Defense Headquarters in Abuja said of Thursday night's attacks.

Nigeria's President Muhammadu Buhari on Thursday called for an end to "unruly behavior" in the country, saying progress could not happen without a change in citizens' attitudes.

The call, made in his first Independence Day address as civilian president, will likely remind some of his time as military ruler in the 1980s, when he cracked down on so-called "indiscipline".

Nigeria was on Tuesday warned that violence could resume in the oil-producing south, exacerbating pressure on already stretched resources by Boko Haram in the north,and reduced crude revenues.

The International Crisis Group said the root causes of the insurgency in the strategic Niger Delta remained "largely unaddressed" and action was required to maintain the fragile peace.

Nigeria's military said more than 200 members of Boko Haram surrendered Friday as troops regained control of the northeastern town of Banki, from where attacks had been launched into Cameroon.

"Over 200 members of the terrorist organization Boko Haram have surrendered today (Friday) to the Nigerian troops in Banki town," army spokesman Sani Usman said in a statement.

Nigeria's military on Wednesday said troops had rescued 241 women and children during operations against Boko Haram Islamist militants in the country's restive northeast.

The women and children were picked up on Tuesday as soldiers cleared what the military said were "terrorist camps" near Banki in Borno state, close to the border with Cameroon.

More than 20 people were killed in a bomb attack in the garrison town of Monguno in remote northeast Nigeria, witnesses and the country's main relief agency said on Wednesday. 

Ibrahim Abdulkadir, northeast coordinator of the National Emergency Management Agency (NEMA), said "between 25 and 28" were killed in Sunday night's attack while locals said at least 21 died.

Nigeria on Wednesday imposed tight movement restrictions in the restive northeast after Boko Haram bombings that killed more than 100 raised fears of fresh attacks over the Eid al-Adha festival.

The military said the use of all vehicles would be banned throughout Borno state during the Muslim festival, which is known as Sallah in Nigeria and marked with two days' public holiday from Thursday.

At least 54 people were killed in a series of blasts in the northeast Nigerian city of Maiduguri, police said on Monday, the latest attacks by Boko Haram militants on "soft" civilian targets.

The attacks targeted the Ajilari Cross evening market area and neighboring Gomari, hitting worshipers at a mosque and football fans watching a televised match.

Bright orange flames flare upwards from a pencil-thin chimney at the Port Harcourt Refining Company, sending thick black smoke into the white clouds above Nigeria's southern oil hub.

On the ground, workers in boiler suits and hard hats inspect the tanks, valves and gauges around the metal pipes that stretch up, down and across the facility.

Some 500,000 children have been forced to flee Boko Haram militants in the last five months after an upsurge in attacks in Nigeria, Cameroon, Chad and Niger, the UN children's agency said on Friday.

The additional numbers of children made homeless has taken the total number of youngsters in the Lake Chad region who have been forced to flee to 1.4 million, Unicef said in a statement.