The explosion, a witness claimed, was so loud, it reverberated all over the city.
One witness said the bomb explosion took place at the motor park, close to the main vegetable market in the town, when traders were already closing business for the day and heading home.
He also feared many were killed but could not give the number of casualty as first responders have arrived at the scene, which has been cordoned off by security agencies.
The attack comes about 72 hours after President Muhammadu Buhari visited Internally Displaced Persons in Yola and assured them that the Boko Haram insurgency would soon be a thing of the past.
The last time an explosion was heard in Yola was in October.