At least 86 people were killed in explosions blamed on Boko Haram last week alone, all of them at crowded bus stations in the North-east, wider north and also in Plateau State.
The style of attack — using either explosives left in bags or suicide bombers — has prompted the government in Abuja to issue a warning for increased vigilance at "soft targets".
But with elections on March 28 that Boko Haram has already vowed to disrupt, security experts said there would be renewed fears about the safety of voters, particularly at polling stations.
“I think it's safe to say that as multinational counter-insurgency operations continue in the North-east, Boko Haram will intensify its urban terror campaign,” Ryan Cummings, chief Africa analyst at Red24 risk consultants, told AFP.
“Boko Haram will know that it lacks the resources or capacity to engage the Nigerian Army and its allies in conventional warfare, so its retributive attacks will increasingly focus on asymmetric warfare, which is resource-light but nevertheless damaging.”
Attacking towns and cities recalls Boko Haram’s previous tactics before it began capturing and seizing territories in the North-east in mid-2014, declaring some part an Islamic caliphate.
Cities such as Kano and particularly the Borno State capital, Maiduguri, were hit regularly until the government declared a state of emergency in May 2013 in three North-eastern states.
The military and civilian vigilante forces managed to push the rebels out into more remote, rural areas, where violence continued and in many cases intensified.
With soldiers thin on the ground in the countryside — and with apparent dissent in the ranks about the provision of weapons and equipment — Boko Haram launched its unprecedented land grab.
But since the attack on Baga on January 3, where hundreds of civilians, if not more, were killed, and rebel strikes in Chad and Niger, there has been a concerted fight-back.
Nigerian troops, aided by soldiers from Cameroun, Chad and Niger, have bombarded rebel strongholds in North-east Nigeria and have recaptured territories, including Baga last weekend.
President Goodluck Jonathan visited the ravaged town on the shores of Lake Chad on Thursday, telling troops that the conflict, which has killed more than 13,000 since 2009, would soon be over.
Observers have framed the claimed successes against the backdrop of upcoming elections in Nigeria, which were postponed for six weeks from February 14 because of the ongoing military operations.
The National Security Adviser (NSA) Sambo Dasuki said at the time that troops would not be available to provide security on polling day.
Boko Haram leader Abubakar Shekau vowed in a recent video that the elections, now scheduled for March 28, “will not be held, even if we are dead”.
Militants have even distributed fliers calling on people not to vote.
Mark Schroeder, a political and security risk analysts in Stratfor, said the recent bombings in Kano — the north's biggest city — and the central city of Jos, raised a new security threat.
“The Nigerian military, with renewed government backing, may achieve the easy steps of a counter-insurgency of asserting control in remote urban areas of the North-east,” said Schroeder.
“But stopping Boko Haram from counter-attacks against civilians elsewhere is very difficult.
“You could say Boko Haram is merely being displaced while the Nigerian government publicises gains in Baga and elsewhere.”
Boko Haram, which has invigorated its propaganda campaign with slick, Islamic State-style videos, will no doubt claim that such attacks put paid to government's claims that it is being defeated.
Cummings argued that the return to guerrilla tactics in towns and cities could stretch security resources.
Abdullahi Bawa Wase, a Nigerian security analyst who tracks the Boko Haram conflict, described the bombings as “desperation” on the part of the militants.
But he noted that such attacks had not stopped during the change in tactics to seize territory but were now taking place in tandem with hit-and-run strikes, “to show they still have the capability”.
“We are only going to see an intense increase of this bombing in the next weeks,” which could possibly force another postponement in the election, he added.
In response to the increased spate of bombings in the north, the military have issued an advisory call on Nigerians to be extra vigilant.
In a statement yesterday from PR Nigeria, a media consulting firm for government security agencies, it quoted top intelligence sources as stating that following the routing of the terror group from towns and villages in the North-east, “Boko Haram terrorists have once again reverted to the use of suicide bombers in its evil campaign against Nigeria”.
The statement added: “A security alert has thus been sounded for Nigerians to be vigilant and on the lookout for potential suicide bombers already brainwashed and probably drugged by the terrorists.”
PR Nigeria gathered from top intelligence sources in Abuja that Boko Haram members, in their desperation to escape the military onslaught and in a bid to retaliate such offensive, has resorted to suicide bombings which was their hit-and-run tactic used for some years until 2014.
“This time around, however, the terrorists have been using children and teenagers especially female to perpetrate their nefarious activities on soft targets in some northern states. Their major mission is to attack soft targets like bus parks, schools, worship centres and markets, among others, to extract maximum casualties among the citizens,” the media consulting firm said.
It added that some of the explosive devices used for suicide bombings where stolen from quarry industries within and outside the country.
“The collaboration against religious extremism forged by countries around the Lake Chad Basin has so far frustrated the insurgents that it is now difficult for them to strike in Nigeria and run to neighbouring countries who have sealed off their borders against the terrorists.
“In the last two weeks, several towns and local governments in Borno, Yobe and Adamawa States including the training facilities and logistics dumps of the insurgents have been reclaimed by gallant Nigerian troops,” it said.
Also speaking on the development, the Directorate of State Security Service (DSS) has called on Nigerians to be very vigilant whenever they are in crowded areas.
In a release issued at the weekend, the DSS spokesperson, Marilyn Ogar, said: “It has become evident that following the successful sustained air raids and intense combat operations by the military on insurgents’ positions in the northeast, which have effectively degraded the capacity of the terrorists, its members are now in disarray and have resorted to taking out their anger on hapless civilians and soft targets.
“This development accounts for the recent spate of attacks recorded in Yobe, Kano, Borno and Plateau States with intent of distracting security forces.
“Accordingly, this service wishes to advise members of the public to be vigilant especially in crowded environments and when travelling. Commuters should desist from boarding unmarked vehicles along the road and only use designated bus parks.
“We also reiterate our call on bus park managers to ensure proper screening of vehicles, persons and luggage entering their premises. They should also look out for new faces who show up as drivers and conductors,” she said.
