Every year, hundreds of thousands of migrants enter Europe by sea from the South — and thousands from those groups drown as they attempt to make the voyage from places like Libya, Mali and Egypt.

At least 700 people are believed to have drowned after a boat was shipwrecked in the Mediterranean Sunday.

“It’s a problem that’s been building for years, and the numbers have continued to rise,” says Chris Morris, with the BBC. “They’re not all political refugees, many of them are economic migrants.”

Most people attempting the journey are trying to escape the violence and poverty in their native countries and find better job opportunities.

“London, in particular, is a magnet because it’s Europe’s genuinely international city,” Morris says. “It’s a place where many people from many countries have friends, or relatives, or somebody from the village who has said, ‘if you manage to get here, I’ll get you a place where you can kip on the floor and my cousin will give you a job at his bakery.'”

This disaster has prompted much criticism over the European Union’s response to the dangers migrants face crossing the Mediterranean. There’s no final count yet of exactly how many people drowned in yesterday’s sinking of that migrant ship.

What is clear, however, is that people will risk their lives to get out of where they are.