After aerial footage from the Italian coastguards revealed what looked like a grisly murder scene on board a migrant boat police have swooped and made five arrests.
The five men are suspected people traffickers and are facing charges of torture, while one is also accused of murder.
Survivors from the three boat group, which set off from Libya heading for the Italian coast,
said once they reached international waters the smugglers ordered everyone on board to sit down and take off their hats.
When one young man did not understand the orders and failed to obey, he was shot dead.
Three Nigerian suspects were arrested in Agrigento, and two Libyans in Catania. All had been the subject of an ongoing police investigation by Italian police and coastguards.
Three hundred and ninety-four people were rescued.