At least 15 people have been killed and five others injured when a minibus collided with two heavy trucks in western Russia's Ulyanovsk region on Sunday.The driver of a truck drove into the oncoming lane and crashed with the bus, TASS news agency reported.The injured have been hospitalized and an investigation is underway.At least 15 people have been killed and five others injured when a minibus collided with two heavy trucks in western Russia's Ulyanovsk region on Sunday.The driver of a truck drove into the oncoming lane and crashed with the bus, TASS news agency reported.The injured have been hospitalized and an investigation is underway.