- There were either one or two female suicide bombers, authorities said
- President Jonathan had left an hour earlier, police said
Police said one female bomber detonated explosives, killing herself and another person. But rescuers and medical sources said both women were suspected to be suicide bombers.
The number of injuries was also unclear. Fwaje Atajiri of the Gombe Police Command said six people had minor injuries. Rescuers and medical sources reported 18 people injured in a blast were being treated at a hospital.
The bomber was "a long distance" from where the rally had taken place, due to security measures, Atajiri said. Jonathan had left an hour earlier and was already out of the city when the blast occurred, he added.
There was no immediate claim of responsibility for the blast. Gombe, in northeastern Nigeria, is one of the sites that has faced repeated attacks blamed on the militant Islamic group Boko Haram