"What were once very informal ad-hoc networks, moving people from place to place, are now offering a higher range of services including document fraud."
Once in the country, migrants are often forced to hand over their money and passports, leaving them at the mercy of the traffickers. Ali from The Gambia was forced to board an unsafe boat.
"The Libyan man lied to us," he told the BBC. "He said it was a big boat. We all paid 1,000 dinar (£488, $728). When we got to the boat, he forced us to enter with a gun, if you don't enter he will shoot you."
"The Syrian migration flow changed the game as far as human smuggling was concerned in Sub-Saharan Africa, because the Syrians had more money to pay.
"They were ready to put down several thousand dollars at a time, whereas the African migrants could never pay more than $200 or $300. Those groups that could respond to that need began to profit very quickly and they were making millions of dollars."