Three bombings, including one by a female suicide attacker, killed at least 47 people in Maiduguri on Saturday, in the latest violence blamed on Boko Haram.
Many children were among the dead and at least 50 others were wounded in the explosions that hit two crowded markets and a busy bus station.
The Nigerian Islamist militants have relentlessly attacked Maiduguri throughout their six-year uprising, which has cost more than 13,000 lives and security forces in the city have struggled to contain the bloodshed.
Nigeria has since last month claimed key victories over Boko Haram in an offensive being waged in cooperation with forces from neighbouring Cameroon, Chad and Niger.
Several towns and villages in the northeast previously captured by the insurgents have reportedly been taken back by government troops and experts have said that in response Boko Haram was likely to increase attacks on civilian targets in major cities.
– Markets, bus station attacked –
A woman with explosives strapped to her body blew herself up at roughly 11:20 am (1020 GMT) when she got out of a motorised rickshaw at Maiduguri’s Baga fish market, said the head of the fisherman’s union, Abubakar Gamandi, who was at the scene.
“The bomb was devastating because it occurred at a crowded area,” said Jamuna Jarmi, a grocery seller.
Boko Haram has deployed women and even girls as young as seven as human bombs in attacks across northern Nigeria in recent months, prompting global condemnation, including from other jihadist groups.
About an hour later another blast rocked the popular Monday Market, causing chaos as locals voiced anger at security forces who struggled to control the scene.
Just after 1:00 pm a third blast hit a used car lot which is attached to the busy Borno Express bus terminal.
There were indications that the second and thirds blasts were also carried out by suicide bombers but details were not immediately clear.
Gamandi, who spoke to AFP from the Maiduguri General Hospital where he was helping coordinate rescue efforts gave the toll of 47 dead and 50 wounded for the three blasts.
His figures were confirmed by a nurse at Maiduguri General and a vigilante leader in Borno, Danlami Ajaokuta, whose civilian fighters have been working with military across the northeast in fighting Boko Haram.
Ajaokuta said the security forces had ordered the closure of all businesses across the city given the apparently coordinated nature of the bombings and the fear that more could be coming.
Borno State’s Justice Commissioner Kaka Shehu confirmed all three attacks but declined to discuss casualty figures.
He immediately blamed Boko Haram, saying the latest bloodshed was in response to the defeats suffered by the insurgents in recent weeks.
“The terrorists are angry with the way they were sacked from towns and villages and are now venting their anger,” Shehu told AFP.