More than 200 migrants were feared dead after two overcrowded fishing boats carrying up to 500 migrants capsized off Zuwara coast in western Libya.

The first boat carrying 50 migrants sank early on Thursday, according to BBC. Around 400 migrants were onboard the second boat when it sank while on its way to Europe.

Officials said Libyan coastguards rescued around 200 migrants from the fishing boats, according to Reuters. More than 140 rescued migrants were sent to a detention center in Sabratha.

A Libyan coastguard vessel found up to 160 bodies floating in the sea about a kilometer from the city of Zuwara, reported Guardian. Forty other bodies were found in the hold of the boat.

"I started checking people for signs of life, and I stopped counting after 24... I just quickly checked for signs of life and moved on. There was water in the boat, some people were half in the water, face down," Dr. Simon Bryant of Doctors Without Borders told AFP in a Skype interview.

Zuwara coast in west Libya, bordering Tunisia, is a major transit point for smugglers sending migrants from Africa to Italy, according to Standard. The victims, mainly from Sub-Saharan Africa, were fleeing violence in their countries for a better life in Europe.

The United Nations said more than 2,400 migrants died so far this year trying to cross the Mediterranean to reach Italy.