UN Human Rights spokesperson Jeremy Laurence stated on Friday that countries need to investigate and prosecute people smugglers and human traffickers after 400 to 750 migrants were on a fishing boat that capsized 50 miles from Pylos, a southern coastal town in Greece.

The disaster resulted in 78 people deceased and 104 survived, but many more are missing. The UN migration agency said that migration routes from the Middle East and North Africa to Europe are often dangerous and urged countries to cooperate to ensure the safety of migrants. Fedrico Soda, UN migration agency director, said that there need to be a “collective effort” for proactive search and rescue on the coast. Greece is one of the main routes to the EU for refugees and migrants from Africa, Asia and the Middle East and has faced significant criticism from the EU and UN for their migrant “pushbacks” last month.

Witnesses and volunteers said that most migrants were from Libya and Syria. The death toll has steadily increased as more migrants were found trapped under the vessel. Local news reported that the boat was destined for Italy after leaving the Libyan city of Tobruk, and 9 Pakistani men have been located and arrested on suspicion of trafficking offenses which caused the shipwreck.

Laurence reiterated the need to open up more migration channels in Greece to avoid future tragedies at sea, and called for independent monitoring and oversight of migration practices and policies.