Authorities are looking for three men who stabbed another man to death on a bus in Highland Park on Monday night.
The men then walked to the rear of the bus and got into an argument with a man who was alone, authorities said.
During the argument, one of the three men pulled out a knife and fatally stabbed the man in the chest. The bus came to a stop at Figueroa and Meridian streets and the three men ran off, officials said.
"It happened very quickly," Det. Tim O'Quinn told KTLA. "Bus driver was already stopped or stopping at this location. And by the time it had happened, it was over. She reported it. And they had already fled."
The men are believed to be in their 20s or 30s, KTLA reported. O'Quinn told media outlets that it appears the man and the group did not have any prior relationship and that the man was stabbed simply because the argument escalated.
Investigators are expected to review the images from the bus' security cameras for clues.
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