A passenger slashed a Greyhound bus driver's throat as he drove through California last night, causing the vehicle to roll into a field.
At least two people died and dozens were injured, police said.
The attack happened as the driver was doing about 70 mph with a bus full of passengers travelling from Los Angeles to San Francisco.
Emergency crews found more than 50 people injured, 10 of them seriously. One of the dead was the driver, police said.
Authorities said one man, possibly helped by another, rose from his seat and attacked the driver with a knife. The alleged attacker was arrested, Mr Johnson said.
There was no word on what the motive might have been for the attack or if other vehicles were involved in the crash.
AP
