KANO, Nigeria (AFP) - At least 13 people were killed and 53 others injured in north-east Nigeria when an explosive device detonated, a health official and vigilantes helping the military against Boko Haram said Wednesday.
The device was picked up by one of the vigilantes as they travelled back to the town of Monguno, in Borno state, from a military operation against the Islamists in Marte, 40km away.
Salisu Kwaya Bura, chief medical director at the Maiduguri Specialist Hospital in Borno's state capital where the dead and injured were taken, said 13 people lost their lives.
A total of 53 people were injured, of whom 37 were later discharged, he told Borno state governor Kashim Shettima.
Vigilante leader Abdullahi Amadu Bukar earlier told AFP that 12 members were killed in what he described as an "accidental explosion".
"We have brought seven of the dead to Maiduguri this morning (Wednesday) and left five others behind in Monguno," he said.
The vigilantes had been fighting Boko Haram alongside troops in Marte when one of them picked up the explosive device and brought it back to Monguno.
It exploded late on Tuesday as the civilian fighters were examining it on the outskirts of the town, said Bukar, whose account was backed up by another vigilante, Awwal Ibrahim.
Nigeria's military claimed to have liberated Marte and Monguno in February after a ground and air campaign, but Bukar said Boko Haram had returned to Marte once troops withdrew.
Elsewhere, a military truck accompanying technicians from a Nigerian power company to make repairs in the Damboa district of Borno on Monday hit a roadside bomb believed to have planted by the rebels.
Three soldiers were killed in the blast, forcing the team to abandon the mission and return to Maiduguri, 86km away, according to local vigilante sources.