A Greyhound bus caught fire while traveling on Interstate 70 near Greenfield early Monday, closing the highway for almost two hours. The blaze began about 3:30 a.m. on westbound I-70 just east of Mount Comfort Road. The driver told the Indiana State Police the transmission caught fire and the fire quickly spread. No injuries were reported after passengers evacuated the burning bus. Another bus was called from the Indianapolis Greyhound station to pick up the stranded passengers.