The discovery of 72 bodies in a ranch in northern Mexico last month shocked a country already reeling from a brutal drugs war.
It appears that all the victims were migrants from Latin America trying to make it to the United States.
As far as we know, only two people survived the attack.
One of them is an Ecuadorian teenager called Freddy.
He says his group was ambushed by a drugs cartel, and most of them were shot dead.
Freddy was shot in the neck and yet managed to walk 22 kilometres to the nearest police checkpoint to alert the authorities to the massacre.
Freddy is now back in Ecuador and under police protection.
Outlook reporter Irene Caselli visited his hometown to speak to Freddy's sister and his priest about his ordeal and what drives Freddy and others like him to make the perilous journey to the United States.