YOLA, Nigeria — Seven people were killed in an explosion Friday at a Nigerian camp for people displaced by Islamic extremist attacks, an official said.
Thirteen people were also wounded by the explosion in a tent in the Malkohi camp in the outskirts of Yola, capital of Adamawa state in northeast Nigeria, said Saad Bello, the state's National Emergency Management Agency coordinator.
The blast was caused by an improvised explosive device left near the camp's central store, police commissioner Gabriel Adaji said.
President Muhammadu Buhari condemned the attack and directed authorities to tighten security measures in all camps harboring internally displaced persons throughout the country. He urged Nigerians to rise in unison to root out extremists.
"We must not let the desperate and evil-minded criminals have any respite," he said.
No group claimed responsibility for the blast, but suspicion has fallen on the Islamic extremist group Boko Haram, whose uprising has caused the deaths of an estimated 20,000 people since 2009.
More than 1,000 people have been killed since Buhari was elected in March with a pledge to wipe out the militants. At least 2.1 million others have been driven from their homes by the uprising.
Camps for internally displaced are spread out in Adamawa, Yobe and Borno states, which have been hardest hit by Boko Haram's uprising.
The group had seized a large swath of northeastern Nigeria, where it declared an Islamic caliphate. A multinational army earlier this year drove the insurgents out of towns and villages, but suicide bombings and attacks on villages continue.
Adigun reported from Abuja, Nigeria.