At least 19 people have been killed and several others injured when a bus rammed into a tractor and truck in Uganda, officials said.The accident, which happened on Friday night in Uganda's Kiryandongo district, claimed the lives of three juveniles and 16 adults, Xinhua news agency reported citing the police.However, according to officials from the Uganda Red Cross, more people died in the accident and many others who were rushed to the hospital were in critical condition.The bus was heading towards the capital Kampala from the northern Ugandan district of Lira when the accident happened.