Five people were killed and 19 injured in a collision between a passenger bus and a truck late on Tuesday in Cambodia's Pursat province, an official said on Wednesday.The fatal crash took place on the National Road 5 in Krokor district when the back tire of the speeding passenger bus exploded, prompting the bus to hit the truck, district police chief, Em Run was quoted as saying by Xinhua news agency."One passenger was killed on the spot and four died just hours after being sent to hospital due to severe injuries," he said, adding six of the 19 injured people were still in critical condition.The two vehicles were badly damaged in the crash, he added.Road accidents are a leading cause of death in this southeast Asian country, killing an average of six people per day. According to a government's report, road crashes killed 2,265 people last year, up five percent year-on-year.