The nationally recognized Hell's Angels motorcycle club has a "Frisco" chapter that is headquartered in Potrero Hill

The shooting of Mark "Papa" Guardado

On September 2, 2008, Frisco chapter head Mark "Papa" Guardado was fatally shot outside of a bar in the Mission. A member of the Mongols Motorcycle Club named Christopher Ablett turned himself in to the police on October 5 without giving a reason. Authorities were able to trace him to the killing, for which he had a warrant for $5 million, and arrested him. He was later moved him to an undisclosed location and some sources told the Chronicle that Ablett may have been fighting extradition to California, but this claim could not be confirmed. Police could not verify whether the two groups' long-running feud was a motive for the killing.

A massive funeral was held for Guardado on September 15 that was attended by over 1,000 motorcyclists.

More information about the incident and the ensuing funeral can be found at the Chronicle's website:

Police mobilize for Hells Angels funeral, 9/13/08 Guardado's obituary, 9/13/08 Suspect in Hells Angels killing surrenders, 10/7/08 Polite' surrender in Hells Angel's killing, 10/7/08