Spanish police said Friday they had dismantled what they called one of the largest criminal networks involved in smuggling migrants across the Mediterranean, arresting 78 people and seizing 18 high-speed boats. Investigators believe the group was responsible for at least 64 migrant smuggling operations in which more than 2,000 people were brought to Spain, generating profits of more than €24 million ($28 million). Police said the sea crossings were "extremely dangerous", with migrants travelling "crammed together, at high speed, in rough seas". The network charged up to €12,000 per person transported, with some operations involving as many as 50 migrants per crossing, police said. While arrivals to the Canary Islands have fallen in recent months, irregular migration along the western Mediterranean route from Algeria to Spain has increased.