At least 600 children have died this year trying to cross the Mediterranean sea in a bid to escape war, poverty and persecution, Save the Children has said.
Data from the United Nations High Commissioner for Refugees, and newly-analysed by the charity, highlights two children a day on average have died or disappeared between January 1 and September 26 2016.
The figures have been released by Save the Children to coincide with the third anniversary of a shipwreck off the coast of Lampedusa, Italy, in which more than 300 people were killed trying to reach Europe's shores.
Kevin Watkins, chief executive officer of the charity, said it was in the wake of the tragedy that European leaders promised "never again" as images of coffins and the wreck were brought to international attention.
"Since then more than 10,400 men, women and children have died or gone missing trying to reach Europe by sea," he added.
"The Mediterranean sea has become an unmarked grave for children fleeing war, persecution and extreme poverty.
"Just this year, we estimate that at least 600 children have died crossing the sea - a rate of two a day.
"The international community cannot continue to ignore these tragedies - we have an obligation to protect children, be it here in Europe or during their treacherous journeys."
Save the Children said they have been working in Italian ports for more than eight years, helping to keep lone youngsters safe when they arrive on land.
More than 20,600 child refugees and migrants have arrived in Italy since the beginning of the year, with 18,400 of these unaccompanied, the charity said.
In early September, Save the Children extended their operations to help save lives at sea by launching the search and rescue vessel Vos Hestia.
Through this, more than 700 people have been rescued from death in less than a month, including 85 children - some younger than five.