LOS ANGELES (CBS) — The man suspected of punching a fellow rider aboard a Santa Monica Big Blue Bus in West Los Angeles was interviewed by Los Angeles police detectives but not arrested, authorities said Wednesday.

Luis Contreras was hospitalized in critical condition after the April 5 fight as the bus was near Westwood Boulevard and Rochester Avenue.

The man who was questioned is suspected of punching Contreras for stepping on his foot, and Contreras fell out the bus door and hit his head on a curb.

Video showed the attacker punching Contreras in the face.

After interviewing the suspect, West Bureau homicide detectives said they would continue their investigation.

Both men were in their 20s.

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