"When your phone rings and drags you from sleep at five in the morning, there are only two possible explanations: someone dialled your number by mistake, or there is an emergency," writes the AFP photographer Marvin Recinos. "This Friday it was no mistake. On the end of the line was one of my sources, warning me that hundreds of highly-dangerous gang members, or 'pandilleros', were about to be moved from prisons in the east of El Salvador, to the top-security facility of Izalco to the west of the capital."