A child suicide bomber believed to be aged 12 killed at least 10 people after blowing herself up at a market in Yobe state, north-eastern Nigeria.
The incident occurred in the Nannawaji village of Gujba Local Government Area, hours after two suicide bombers killed at least 30 people at a busy fish market in Maiduguri, capital of the restive Borno state.
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.
Borno, Yobe and Admawa states mostly bear the brunt of the insurgency which has claimed thousands of lives since 2009.
The Islamists also carry out attacks in other states such as Kano, Katsina and Yola.
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.
President Muhammadu Buhari, a former military chief, vowed Nigeria will do anything it can to defeat the deadly insurgence and find some 220 girls who were kidnapped by Boko Haram in Chibok, Borno state, in April 2014.
Anti-terrorism fight marred by human rights abuses
Amnesty International warned that the regional anti-terrorism fight might lead to human rights abuses. The group warned that 84 children - some as young as five - have been detained for months in Cameroon, following a raid in December 2014 on Islamic schools which authorities suspected were Boko Haram training camps.
Meanwhile, Chad announced it would start rounding up foreigners and beggars following a deadly attack in the capital N'Djamena that killed dozens earlier in June. In the aftermath of the attack, which was blamed on Boko Haram, Chad announced it carried out strikes in northern Nigeria and destroyed six Boko Haram camps. However, Nigeria said the territories targeted by the air strikes were not within the Nigerian borders.
"There is a real risk of human rights violations in all of the countries threatened by Boko Haram," Steve Cockburn, Amnesty's deputy regional director, told Reuters. "The countries that are also threatened by Boko Haram do not have to repeat the same mistakes and the same errors as Nigeria," he said, referring to the fact that the Nigerian army has been accused of committing abuses such as detaining and torturing Boko haram suspects.
Reports also warned of arbitrary detention occurring in Niger, where at least 643 people suspected of being linked to Boko Haram have been detained, after the country declared a state of emergency in the southern region of Diffa, where dozens were killed in a Boko Haram attack earlier in June.
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