- A witness says the bomber appeared to be about 13
- Previous bombings in the area have been blamed on Boko Haram
The attack happened in the town of Potiskum, police and hospital sources said.
"We have received four dead bodies and 48 people with several degrees of injuries from the bus station attacked by a suicide bomber," a paramedic at the Potiskum General Hospital said.
The explosion rocked the Tashar Kunne open-air bus station on the outskirts of the town Sunday morning when the young suicide bomber rammed his car into parked buses waiting to fill up with passengers, witnesses said.
"The bomber looked around 13 and he drove his car into buses waiting for passengers, resulting in an explosion that shook the whole area," said grocer Hamza Ibrahim, who witnessed the blast.
The suicide attack caused a stampede in the Potiskum main market which is held on Sunday, with traders and shoppers hurriedly evacuating the market, residents said.
The attack happened a week after two female suicide bombers attacked a mobile phone market in the town, killing four and injuring 46, according to hospital sources.
Potiskum, the commercial capital of Yobe state, has been repeatedly rocked by deadly Boko Haram bomb and gun attacks during the group's armed attempt to establish a strict Islamic state in northern Nigeria.