Italy's foreign minister also confirmed the tragedy on Monday but said that details were still scarce.
"What is sure is that we are again with a tragedy in the Mediterranean, exactly one year after the tragedy we had ... in Libyan waters," Italian Foreign Minister Paolo Gentiloni was quoted as saying by Reuters.
In April 2015, more than 700 refugees died in a similar incident when their boat sank on the way to Italy. The incident caused an international outcry and may have helped to persuade European politicians like German Chancellor Angela Merkel to adopt a more refugee-friendly policy approach last year.
Gentiloni said Monday that more European collaboration was needed. "This is another strong reason for Europe to commit itself not to build walls," he said.
Previously, the Somali ambassador to Egypt had told BBC Arabic that up to 400 refugees traveling on four boats might have died. According to the ambassador, the victims are believed to have come from Eritrea, Ethiopia and Somalia.
Medical organization Doctors without Borders responded to the tragedy in a tweet: "2016, the Mediterranean is a mass grave." The organization could not independently confirm the incident, though.
The refugees who drowned are believed to have traveled on the central Mediterranean route that is used to reach Italy.
A new report released by several British universities alleges that European governments are to blame for some of the deaths that have occurred in the Mediterranean Sea in recent years.
Europe's rescue mission was downsized almost two years ago — leading to at least 1,500 deaths directly related to the measure, the report says. The British study accuses the European Union of "killing by neglect."
More sea arrivals coming from North Africa are expected on Europe's southern shores in the coming months, as they usually increase during the summer.
Moreover, recent measures taken to stop migrants from entering Europe from Turkey could further contribute to the influx of refugees from the south.