The BBC broadcaster reported citing the UN refugee agency (UNHCR) officials that the information about more than 200 drowned people stems from two survivors.
The media outlet added that no bodies of the shipwrecks' victims had been recovered yet.
Europe has been beset by a massive refugee crisis, with hundreds of thousands of undocumented migrants from the Middle East and North Africa fleeing their home countries to escape violence and poverty.
The majority of them cross the Mediterranean Sea and arrive in the European Union using southern EU nations as transit points. According to the International Organization for Migration (IOM), about 333,000 people arrived in Europe via the Mediterranean in 2016, while more than 3,900 migrants died or went missing while trying to reach Europe across the Mediterranean Sea.
