LOS ANGELES (CBSLA.com) — An Encino man pleaded not guilty Friday to four felony counts after police allegedly found three pipe bombs in his vehicle during a routine traffic stop, prosecutors said.

David Patton, 52, faces three counts of possession of a destructive device on a public street or highway and one count of transportation of a controlled substance, methamphetamine, according to the Los Angeles County District Attorney’s Office.

Patton was pulled over by police March 19 on Devonshire Street and Reseda Boulevard in Northridge when officers found what appeared to be a pipe bomb, Deputy District Attorney Sean Carney said.

A more thorough search of the defendant’s vehicle turned up two additional pipe bombs, he added. Once the devices were confirmed to be explosive, the intersection was shut down and nearby residents and businesses were evacuated.

If convicted of all charges, Patton faces a maximum possible sentence of over six years in jail. He was being held on $530,000 bail.