ROME — A Tunisian captain who was piloting a fishing vessel crammed with migrants that collided with another ship, resulting in the deaths of about 700 people traveling to Italy from Libya, was sentenced on Tuesday to 18 years in prison.

The captain, identified as Ali Malek Mohammed, 28, was convicted by a court in Catania, Sicily, of multiple manslaughter, human trafficking and causing the disaster in April 2015, the Mediterranean’s deadliest known shipwreck.

Prosecutors said he had steered the fishing boat into a Portuguese freighter, the King Jacob, off the Italian island of Lampedusa. The King Jacob was sent to the area to help after the Italian authorities received an emergency call, prosecutors said.

The victims were part of a huge influx of migrants fleeing war and economic desperation who have risked their lives in an effort to reach Europe. More than 4,740 migrants died trying to cross the Mediterranean in 2016, according to an estimate by the International Organization for Migration, far surpassing the 2015 total of 3,660 deaths.