Pastor Manuel Rivera's voice echoes through the crowded courtyard in the notorious San Francisco Gotera prison in El Salvador, as hardened criminals weep and bow their heads in prayer. Brutal 'mara' street gangs and chronic poverty have made El Salvador one of the most murderous countries on the planet, but the growth of evangelical Christianity behind bars is giving gangsters a way to break the spiral of violence. Rivera, an ex-hitman from the powerful Barrio 18 gang, speaks to rows of men with spidery black tattoos on their arms, necks and faces, delivering a message of salvation: God had rescued them from violence. Returning to gang life would mean death. REUTERS/Jose Cabezas SEARCH "CABEZAS GOD" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. Matching text: EL SALVADOR-VIOLENCE/