Under arrest: a couple from Petaluma who Santa Rosa police believe were selling heroin out of their car. Pedro Lopez and his wife Joann Guzman were tailed by detectives as they drove around to various shopping center parking lots in Sonoma County. They found 6 ounces of heroin after detaining them, and a subsequent search of their home uncovered two pounds of heroin and cash. Lopez had been on the police radar since July. Detectives believe they were selling heroin at the parking lots as their two kids were in the car. They’ve been placed with a family member.