CONAKRY, Guinea — A suicide bomber disguised as a student detonated a bomb at a boarding school in northern Nigeria Monday morning, killing at least 48 boys who were between 10 and 20 years old, officials and witnesses said. About 80 other boys were wounded.
The bomber was wearing a school uniform when he appeared at the morning assembly at the Government Senior Science Secondary School in Potiskum, said Mohammed Abubakar, a local journalist who had returned from the scene of the bombing.
When the school prefect asked the bomber why he was not wearing the school's badge, he knelt down and detonated the bomb, Abubakar said.
Witnesses said the school was a chaotic scene of dead and maimed children, and the local hospital was packed with the wounded.
Northern Nigeria has long been crippled by an Islamist insurgency, and the militant group Boko Haram has targeted non-Koranic schools for at least the last three years, killing dozens of students and kidnapping hundreds of others. Monday's bombing was one of the worst such attacks to date.
In Potiskum alone, a major market town on the principal east-west axis in Nigeria's north, Boko Haram is believed to have attacked about 10 schools. In just over a year, five other schools in surrounding Yobe state have been assaulted by fighters believed to be members of the group.
In February, at least 40 were killed at a boarding school in nearby Buni Yadi; in July of last year, 42 students were killed in an attack at a government school in a village near Potiskum.
Boko Haram did not claim responsibility for Monday's bombing — it rarely does for individual attacks — but it has made what it calls "Western education" a particular focus of its bloody campaign against civilians and soldiers.
The latest attack occurred just before 8 a.m. Monday, and the students at the 2,000-student school had gathered for morning assembly. A slight man of around 25 wearing the school's uniform appeared.
"He entered the assembly ground," said Yahaya Wakili, a nearby resident. The students "were waiting for the principal and the other teachers."
According to several accounts, the man was carrying a heavy bag, prohibited under school rules. He told the prefect it was for carrying his books.
A student who was there, Mohammed Musa, said, "We were at the assembly ground waiting for our teachers to address us for the beginning of the week and suddenly I heard a very heavy sound."
The blast resounded throughout the neighborhood. "It was very, very loud," Wakili said.
Abdulkareem Adam, another student, described "so many dead bodies littered on the ground."
Abubakar, who went to the school immediately after the blast, said, "I saw many wounded schoolchildren." He described ghastly injuries and "people running away with wounds."
Despite the repeated school attacks and multiple student deaths, Nigeria's military has not been deployed to guard the schools of the north, and there was no military presence before the blast at the Potiskum school Monday, Abubakar said.
The school was "not safe. It is porous," he said, adding that even the school gate was broken.
Wakili said there is "no fencing," adding, "Everybody can come inside the school."
The only protection came from a few local guards armed with sticks, Abubakar said.
Parents who gathered at the school after the bombing angrily told the military to leave, saying they "no longer had confidence" in the soldiers "because they were not able to protect their lives and property," Abubakar said. Some news reports suggested rocks were thrown at the soldiers.
Reflecting a rising tide of criticism against the Nigerian government, which has ceded large sections of territory to the Islamist militants in the northeast this year, the governor of Yobe state issued a strongly worded statement Monday saying it was "not just enough for the federal government to condemn the almost daily rounds of violence." Instead, he said "urgent action" was needed.
Last month, the Nigerian government said that Boko Haram — whose name means ''Western education is sinful'' in the Hausa language — had agreed to a cease-fire and that 200 schoolgirls it had kidnapped earlier this year would be released imminently. Instead, the militants have stepped up the number and deadliness of attacks.
The United States and the United Nation strongly condemned Monday's attack.
''Our sympathies and thoughts are with the victims and their families of these latest egregious assaults on innocent civilians by those bent on fomenting violence, extremism, and insecurity in northeastern Nigeria and the region,'' State Department spokeswoman Jen Psaki said.
UN Secretary General Ban Ki-moon expressed outrage at ''the frequency and brutality of attacks against educational institutions in the north,'' UN deputy spokesman Farhan Haq said.