The bullet struck an embankment on the south side of the freeway and no one was hurt in the incident.
By Monday afternoon, Glendora Police traveled to Arcadia, one of the stops of the armored vehicle, and arrested Richard Chairez, 25, of Santa Ana on suspicion of recklessly discharging a firearm. He was held in Glendora Jail on $35,000 bail, said Glendora Police Lt. Brian Summers.
Summers said the suspect was a passenger guard and not driving the armored vehicle owned by Dunbar Armored.
The suspect was angry over domestic issues and upset with working conditions, Summers said. When the guard got out of the vehicle for a delivery at the next stop, the driver called his supervisor to report the incident.
The supervisor called Arcadia Police and the department contacted Glendora Police. Glendora Police responded to the next stop of the armored car and took Chairez into custody, Summers said.