Story highlights The blast took place near where students gathered; police say 79 people were wounded

No one has claimed responsibility for the attack

Police suspect Boko Haram, which has targeted schools teaching Western ideas

The group's five-year insurgency is aimed at establishing an Islamic state‎

Kano, Nigeria (CNN) At least 47 people were killed and 79 were wounded Monday by a suicide bombing outside a school in northern Nigeria, police said.

The attacker was disguised as a student when he set off the explosion in a government boarding school in the town of Potiskum, police spokesman Emmanuel Ojukwu said.

"We suspect Boko Haram is behind the attack," Ojukwu said.

The explosion took place at 7:50 a.m. local time outside the principal's office, where students had gathered for a daily speech.

"We were waiting for our teachers to come and address us at the assembly ground when we heard a huge explosion," student Adamu Ibrahim said.