A media outlet in Nigeria says a suicide bomber has detonated explosives in a northeastern town, killing four people and injuring 35 others.

Channels Television said the attack happened Sunday in Potiskum on Sunday. It was the third such attack this month in Potiskum, the largest commercial center in Nigeria's Yobe state.

Islamic extremists from the Boko Haram group have recently escalated attacks and seized more territory in the northeastern part of the West African nation.