The singer is said to have rear-ended another vehicle in Glendale, California, on Saturday (16Mar13) before driving to L.A., where an eyewitness blocked him until cops arrived at the scene.
According to the Los Angeles Times, the unidentified man saw the smash and followed Murphy because he feared the star "would kill someone with his driving," according to Glendale police.
The female driver whose car was reportedly struck by Murphy's vehicle noted down the rocker's licence plate number before he allegedly drove off after the accident. She received medical treatment following the incident.
Glendale officers have said the 55-year-old Brit appeared to be "very confused", but he denied drinking alcohol and allegedly told cops he had only taken his prescribed pills for depression and felt jet-lagged following a recent flight.
Authorities reported finding a small plastic bag, believed to contain methamphetamine, in the L.A. police patrol car where Murphy had been held.
Murphy was detained on suspicion of causing injuries while driving under the influence of drugs or alcohol, felony hit-and-run and possessing methamphetamine.