In Fresno, local authorities report that heroin is sold in houses. Many of the walk-up buyers are local workers on lunch breaks. The users buy their fix, shoot up in the house, and return to work. Street enforcement operations have forced sellers to relocate indoors. There is little gang involvement with heroin sales in Fresno.
Most sales involve independent distributors who purchase the drug from Mexican wholesale groups.
In Modesto, heroin is sold in houses, from cars, or on street corners. Independent operators sell heroin in Modesto, but organized gangs do not. Mexican black tar heroin is the only heroin available in San Jose. In San Mateo County, Hispanic gangs sell heroin on the street. In Sonoma County, dosage-unit buys of black tar heroin are made from stash houses.