At least 46 students have been killed by a suicide bomber at a school assembly in the north-eastern Nigerian town of Potiskum, police have said.

At least 46 students have been killed by a suicide bomber at a school assembly in the north-eastern Nigerian town of Potiskum, police have said.

A suicide bomber dressed as a student is believed to have caused the blast at the boys' school in Yobe state .
Police suggested the militant group Boko Haram carried out the attack.
Yobe state's governor has shut all public schools around Potiskum and criticised the government for not tackling the group.
In a statement governor Ibrahim Gaidam said: "Urgent action must be taken right now to restore a fast-waning public confidence by doing whatever it takes to stop the escalating violence."
Boko Haram has targeted schools during a deadly five-year insurgency aimed at establishing an Islamic state.
It is waging a sustained campaign to prevent children from going to school. It believes girls should not attend school and boys should only receive an Islamic education.
However thousands of people, not just schoolchildren, have been killed by the group.
On 17 October the Nigerian government claimed to have negotiated a ceasefire with Boko Haram.
But two weeks later the group's leader, Abubakar Shekau, denied these claims and said in a video: "We have not made ceasefire with anyone. We did not negotiate with anyone. It's a lie."
'Devastating attack' The explosion ripped through the assembly hall at the Government Science Secondary School.
Police spokesman Emmanuel Ojukwu told the BBC Hausa service the attack had left 47 people dead, including the suicide bomber. Another 79 were wounded.
Dozens of students were injured so severely medics were unable to save them.

Potiskum is no stranger to attacks - last week a suicide bombing there targeted Shia Muslims Schools in Yobe state have been frequently attacked by Boko Haram militants.
The state is one of three in Nigeria that have been placed under a state of emergency as a result of the group's activities.
Potiskum, one of the largest towns in Yobe, has been targeted before by Boko Haram.
Last week, a suicide bombing killed 15 people in the town.
The bomber joined a religious procession of the rival Shia Muslim sect, before blowing himself up.
Nigeria's police spokesperson told the BBC officers were making progress against the terrorists. "Our mandate is to secure safety and security," he said. "By and large we are making good successes."
The BBC's Will Ross says the authorities are unwilling to admit that the crisis in north-east Nigeria is worsening. The jihadists have taken over towns and villages and there have been some reports of the army fleeing rather than fighting.