A girl thought to be as young as seven has been used as a suicide bomber in an attack that killed her and seven others in northeast Nigeria.
The blast at a market in the city of Potiskum, the commercial capital of Yobe state, was the latest in a string of suicide strikes in which children have been used.
The initial death toll given by witnesses and hospital sources was six - the bomber and five others - but medical sources at the state-run hospital in Potiskum said later two of those injured had also died.
Previous attacks have been blamed on Boko Haram.
Nineteen people injured in the blast were taken to the hospital, said Buba Lawan, a local vigilante leader.
The bombing highlights the severe security challenges facing Nigeria in the run-up to presidential and parliamentary elections on March 28.
President Goodluck Jonathan has conceded his government had initially underrated the Islamist extremist group Boko Haram.
During a swing through neighbouring Chad, Cameroon and Niger, French Foreign Minister Laurent Fabius on Sunday urged Nigeria to entirely commit itself to battling Boko Haram.
"It is necessary that there be full commitment from Nigeria in the fight against Boko Haram," Fabius told reporters in Niger's capital, Niamey.
On Saturday in the Chadian capital N'Djamena, Fabius visited a co-ordination cell set up on a French military base to liaise between Cameroon, Chad, Niger and France.
Paris has promised to increase intelligence-sharing and other assistance to the armies of Nigeria and its three neighbours, which banded together to battle Boko Haram after the extremists expanded their campaign across the region's borders.
Jonathan, who has been in office since 2011, is engaged in a tough re-election campaign against ex-military ruler Muhammadu Buhari.
Voting initially scheduled for February 14 has been delayed for six weeks to give Nigeria's military time to secure the country, despite its failure to beat back Boko Haram in the previous six years.
More than 13,000 people have been killed while more than one million people have been left homeless since 2009 as the Boko Haram militants try to carve out an Islamic state in Nigeria's northeast.
