Nigeria's President Goodluck Jonathan visited the site of what is believed to be Boko Haram's worst massacre on Thursday (26 February) and promised to fight the insurgency.

"I went... to visit communities devastated by the excesses of Boko Haram. I just went to see things for myself," said President Jonathan.

President Jonathan, accompanied by his national security advisor and several senior level military staff, said on Thursday (26 February) he was, "very hopeful this time around that the journey to end (the) Boko Haram insurgency... will soon get to an end."

The president's visit was overshadowed with three separate bombings in the country's central region and restive northeast that left at least 35 dead.

The first bombing occurred in the town of Biu, southern Borno, when a suicide bomber blew himself at a crowded bus station killing 18 people.

Several hours later, explosives were thrown from a moving car at a bus station in the central city of Jos, killing five, followed by a device being thrown at fruit vendors from the same car killing 12, reported AFP News.

As troops from Nigeria, Niger, Chad and Cameroon targeted militants in rural areas, the bombings raised fresh concerns over renewed attacks against vulnerable targets in urban centres.

National Information Centre spokesman Mike Omeri said: "Fugitive terrorists [were] now resorting to attacking soft targets in the face of the onslaught unleashed by the military forces."

Jonathan's administration has faced heavy criticism for failing to prevent Boko Haram's violence and their seizure of increasing territories in the northeast.

Main opposition presidential candidate Muhammadu Buhari said in a speech at the Chatham House International Affairs Institute in London: "Our soldiers have neither received the necessary support nor the required incentive to tackle this problem. Let me assure you that if I'm elected president, I vow to change that.

"We will give them adequate modern arms and ammunition, we will improve intelligence gathering... we will be tough on terrorists and tough on its root causes... in the affected areas.

"No inch of Nigerian territory will ever be in the hands of the enemy."

Nigeria's presidential elections scheduled for 14 February were postponed till 2 March since the troops were occupied in the ongoing counter-offensive and could not offer security on polling day.