The California Highway Patrol says Klein, 31, was seen weaving westbound on the Hollywood Freeway and pulled over early Wednesday. Law enforcement sources say his blood alcohol level was three times the legal limit of .08.
Klein could face a minimum of four days in jail if convicted of a second DUI, TMZ.com reports. Also, under a new law that takes effect in July, Klein – as a multiple offender – could be forced to use a Breathalyzer-type machine to start his car in future.
This is not Klein's first DUI arrest. He also faced drunk-driving charges in 2005 after being pulled over in San Diego County.
Klein, who split with Holmes in 2005, was most recently linked to actress Ginnifer Goodwin. They parted ways in 2008.