SAN FRANCISCO — Erick Lopez, aka “Spooky,” is a hard-core MS-13 gang member who killed two people in San Francisco’s Excelsior district, say federal prosecutors. He is eligible for the death penalty.

Luis Herrera, aka “Killer,” is also allegedly part of MS-13, and he too is eligible for capital punishment. But while prosecutors say Herrera took part in a different murder — the February 2009 killing of Moises Frias at the Daly City BART station — they don’t think Herrera pulled the trigger.