At least 42 people have been killed in two attacks in Borno state carried out by suspected members of terror group Boko Haram.
Who are Nigeria's Boko Haram terrorists?
Boko Haram (recently renamed Iswap) fights against Western influence in Nigeria and aims to impose its version of Sharia law in the country. The group declared an Islamic caliphate in Gwoza, along the Cameroon border, in August 2014.
Boko Haram has raided several cities in the north of the country in a bid to take control of more land.
Three states − Adamawa, Borno and Yobe − have been under a state of emergency since May 2013, due to Boko Haram's attacks.
The group has killed at least 2,700 people since the beginning of 2015. Some 300 have been killed since the beginning of June.
The latest attacks occurred in the remote villages of Debiro Hawul and Debiro Biu in the restive Borno, epicentre of the group's insurgency.
According to witnesses, militants raided the two villages in a convoy of pick-up trucks and motorcycles and shot villagers after looting shops and houses.
"They came around 12:30 am (1130 GMT on Tuesday) and opened fire on the village, which sent people scampering into the bush to escape the attack," a witness told AFP.
"The gunmen slaughtered 22 people who were not fast enough in fleeing and went about looting homes, grain silos and drug stores."
The raids came hours after a child suicide bomber, believed to be aged 12, blew herself up at a market in the village of Wagir, Yobe state, killing at least 10 people.
The incident occurred hours after another two suicide bombers killed at least 30 people at a busy fish market in Maiduguri, Borno's capital.
- Capital: Abuja
- Population: 174,507,53 (2013 census)
- Largest cities: Lagos, Kano, Abuja
- Major ethnic groups: 21% Yoruba, 21% Hausa,
- Languages: English, Hausa, Igbo, Yoruba
- Religion: 50% Muslim, 40% Christian, 10% other
- Currency: Naira (N) 1N = £0.0033; US$0.0050
No group claimed responsibility for the attacks, but suspicions are likely to fall on terror group Boko Haram, renowned for kidnapping civilians - mainly women and children - and forcing them to participate in attacks throughout north-eastern Nigeria, where the terrorists aim to establish an Islamic caliphate.
According to a report by Unicef, the number of suicide bombings involving women and children is increasing in Maiduguri and more suicide bomb attacks have occurred in the north-east since the beginning of 2015 than in the whole of last year.
Newly elected President Muhammadu Buhari has also vowed Nigeria will do all it can to defeat Boko Haram's deadly insurgence in the north east and find the 220 girls who were kidnapped by the militants in Chibok, Borno state, in April 2014.
The Nigerian government is being aided by mercenaries and troops from Chad, Benin, Niger and Cameroon in its offensive and has scored some successes since the military co-operation started in February.
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