Three persons were killed on the spot and over 20 injured when a mini truck in which they were travelling, collided head on with a speeding truck at Salebhata in Balangir district late on Friday night.According to reports, a group of people from Guderkanta village of Dunguripali block had gone to attend a marriage feast to a nearby village by a mini truck. On their return, the driver lost control of the vehicle, which hit a truck coming from the opposite direction.The injured were rushed to the VSS Medical College Hospital at Burla.