Lagos: Nigeria`s military on Wednesday said it had arrested a suspect thought to have planned Boko Haram attacks in the central city of Jos and northern city of Zaria that killed more than 70 people.
Army spokesman Sani Usman said a security cordon put in place after the attacks led to the arrest of "the mastermind" and two accomplices in the northeastern state of Gombe.
"The terrorist kingpin and his colleagues who (were hiding) in a trailer while trying to evade checks were fished out by troops of the Nigerian Army," he added in an emailed statement.
Sunday night`s attacks in Jos saw a mosque hit with bullets and a rocket-propelled grenade fired, while a restaurant popular with travellers from the restive northeast was also targeted.
Mohammed Abdulsalam, coordinator for the National Emergency Management Agency (NEMA) in Jos, told AFP on Wednesday the death toll had risen from 44 to 51.
On Tuesday 25 people died when a suspected suicide bomber detonated his explosives at a government office in Zaria, Kaduna state, as public sector workers queued for identity checks.
Boko Haram has increased the frequency and intensity of its attacks since Muhammadu Buhari became president on May 29, vowing to crush the militants.
In that period more than 550 people have died, according to an AFP tally.
The upsurge in attacks has prompted Nigeria`s authorities to issue public warnings for vigilance to the general public, particularly in crowded places such as bus stations, markets and mosques.