Five children, four girls and one boy, were behind a series of blasts in the north-eastern Nigerian city of Maiduguri on Thursday, sources say. 
 
 Fifteen people, including the bombers, died and more than 35 were injured in the attacks at a mosque and house of vigilante leader, they said. 
 
 More than 100 people died in similar attacks in the city two weeks ago. 
 
 Maiduguri is where Boko Haram Islamist militants were first based when they began their insurgency six years ago. 
 
 Some 17,000 people are said to have been killed in that time and attacks by the group have intensified since Muhammadu Buhari became president in May, vowing to defeat the insurgents. 
 
 The BBC's Abdullahi Kaura Abubakar in the capital, Abuja, says people were waiting for the final evening prayers when three suicide bombers struck the mosque. 
 
 The girl carrying the fourth bomb ran off into the nearby bush where her explosives detonated, killing her. 
 
 The vigilante leader was not at home when a suicide attacker struck his house, our reporter says. 
 
 Witnesses and security sources said the children were aged between nine and 15. 
 
 Earlier reports said all five of the bombers were girls. 
 
 Our correspondent says the attacks in Maiduguri, the capital of Borno state, come as the military says it is winning the war against Boko Haram. 
 
 In June, the military's headquarters were moved to the city as President Buhari wanted to centralise operations against the militants. 
 
 This year, the security forces have reclaimed most of the territory captured by Boko Haram fighters and freed a number of people kidnapped by the militant group. 
 
 But the boosted regional multinational force - central to Mr Buhari's strategy in defeating the militants - has not yet started operations in earnest because of reported funding difficulties, our reporter says. 
 
 Mr Buhari has given his newly appointed security chiefs until mid-November to defeat the fighters, who now have ties with Islamic State group. 
 
 More than 200 schoolgirls kidnapped in April 2014 from the town of Chibok in Borno state have also yet to be found. 
 
 Boko Haram at a glance: 
 
 Image copyright AFP 
 
 Founded in 2002, initially focused on opposing Western-style education - Boko Haram means "Western education is forbidden" in the Hausa language 
 
 Launched military operations from Maiduguri in 2009 
 
 Thousands killed, mostly in north-eastern Nigeria, hundreds abducted, including at least 200 schoolgirls 
 
 Joined so-called Islamic State, now calls itself IS's "West African province" 
 
 Seized large area in north-east, where it declared caliphate 
 
 Regional force has retaken most territory this year 
 
 Using football to tackle Boko Haram 
 
 Who are Boko Haram? ||||| They’re called “suicide” bombers, but the children sent by Nigerian terror group Boko Haram to detonate bombs and kill people are not given a choice. They are mostly girls, some as young as 8. 
 
 Boko Haram’s cruelty to children — its killings, abductions, coerced marriages, slavery and forced “suicide” bombings — plumbs a horrifying low that other Islamist extremists have yet to reach. 
 
 The group’s leader, Abubakar Shekau, shocked the world with his grim smile as he announced that 276 schoolgirls abducted in Chibok, in Nigeria's Borno state, in April 2014 would be sold into slavery. 
 
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 Since then the group has ramped up the use of children as bombers, according to a report Tuesday by UNICEF called “Beyond Chibok.” 
 
 Last year, 44 children were sent by Boko Haram to detonate bombs in crowded places such as mosques, markets and a displaced persons camp, up from four the year before. Three quarters of them were girls. 
 
 “The use of children, especially girls, as suicide bombers has become one of the defining and alarming features of the conflict,” the report said. 
 
 Between January 2014 and February 2016, there were 40 “suicide” attacks involving one more children, 21 of them in Cameroon, 17 in Nigeria and two in Chad, according to the report. 
 
 Women and girls in the regions wear long loose gowns, making it easy to conceal explosives. 
 
 In January, two female bombers hit a mosque in Kolofata, northern Cameroon, killing at least 10. A few days later a boy detonated a bomb at a mosque in Nguetchewe village in Cameroon, killing four. In March, 22 people died in Nigeria after two female bombers detonated devices. 
 
 In February, 58 people were killed in Dikwa, Nigeria, when two females detonated bombs. A third member of the bombing mission decided not to set off her explosives, because she spotted her family in the camp, according to Nigerian media citing authorities. 
 
 Boko Haram is fighting to establish an Islamic state in Nigeria and last year pledged allegiance to the Islamic State extremist group. In recent months, military forces from Nigeria and neighboring countries have freed thousands of people, including women and girls who had been abducted and forced to become sexual slaves. 
 
 Doune Porter, UNICEF spokeswoman in Nigeria, last week met girls in Maiduguri, the capital of Nigeria's Borno state, who had been imprisoned by Boko Haram, many of them traumatized by repeated rapes and abuse. 
 
 Some had seen their friends forced by Boko Haram to carry out bombings. 
 
 Porter said the bombings couldn’t be called suicide attacks because the children were either forced to carry them out or were not of an age to understand the consequences of their actions. Some may have been misled or brainwashed by adults. 
 
 “I met one girl who told me two of her friends were forced to carry out bombings. She said they didn’t want to do it. They were forced to do it. 
 
 “One of them told me that girls who had refused to ‘marry’ Boko Haram soldiers had been forced to act as so-called ‘suicide’ bombers,” Porter said. “They were all girls who were captured by Boko Haram when it took over their villages. 
 
 “Now, many of them are facing fear from their communities. That’s one of the terrible, tragic effects of using children to carry out bombings. When they return to their communities, they very often face stigmatization and isolation because they’re seen as being tainted by Boko Haram.” 
 
 The report warned that abducted girls faced the risk of being rejected and even killed by suspicious communities. 
 
 Many of the girls and women forced into marriage with Boko Haram fighters are in displaced persons camps in Maiduguri. Some told Porter their parents had been killed in Boko Haram attacks. Others didn’t know where their parents were. But some had found their parents and been accepted by them. 
 
 “They’re all very traumatized," Porter said. "They have gone through the most awful beatings and rapes. Some of them have been raped by many different people, some by just one man. Some of them are pregnant or have had children. 
 
 “One girl told me she was held in a house and there were 20 girls and women ranging from 12 years old to middle-aged women. And Boko Haram soldiers would just come and rape them.” 
 
 One 17-year-old from Cameroon was visiting her mother in a Nigerian village when Boko Haram attacked, abducted her, locked her in a house and forced her to “marry” a fighter, according to the report. She became pregnant and gave birth to a boy while in captivity. 
 
 When she was freed and arrived in a displaced person’s camp, she faced suspicion and hostility. 
 
 “When I arrived at the camp, I didn’t have anything,” she told UNICEF researchers. “I had to borrow from people. Some women would beat me, they would chase me away. They said, ‘you are a Boko Haram wife, don’t come near us!’ 
 
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 “If I used their washing basin to clean, they would say, ‘You are Boko Haram wife, don’t touch our basin’. Everywhere I went, they would abuse me and call me a Boko Haram wife. I felt as if I was neglected; I did not have anybody to help or support me. 
 
 “When I feel sadness in my heart, sometimes I cry and wipe my tears away.” 
 
 About 2.3 million people, including 1.3 million children, have been displaced by the crisis, according to UNICEF. More than 670,000 children are not able to go to school because of the conflict. 
 
 Boko Haram attacks prevented farmers from planting crops, herders from keeping cattle and fisherman from going to fish in Lake Chad. UNICEF last year assisted 93,000 in the region with severe chronic malnutrition. 
 
 Follow @RobynDixon_LAT for news from Africa. 
 
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– Five children perpetrated the suicide bombings that killed 15 people, including themselves, and injured at least 35 others Thursday in the Nigerian city of Maiduguri, the BBC reports. Witnesses say the child suicide bombers—four girls and one boy—were between the ages of 9 and 15. Three of the bombs exploded at a mosque just before final evening prayers. The girl with the fourth bomb intended for the mosque ran off but died when her bomb also exploded. The fifth child suicide bomber struck the house of a vigilante leader, who was not home at the time. The BBC reports Boko Haram is believed to be behind the attacks Thursday in Maiduguri, which was the Islamist militant group's original base six years ago. Boko Haram is stepping up attacks against civilians as the Nigerian military has begun seeing success in fighting them, according to Al Jazeera. A wave of attacks in Maiduguri less than two weeks ago killed at least 117 people. Earlier this week, Amnesty International called for greater protection for citizens from Boko Haram attacks. The group is believed to have killed at least 17,000 people since beginning attacks in 2009.