A woman cries after being rescued in the Mediterranean Sea about 15 miles north of Sabratha, Libya, on July 25, 2017. More than 6,600 migrants and refugees entered Europe by sea in January 2018, according to the UN migration agency, and more than 240 people died on the Mediterranean Sea during that month.
Refugees and migrants get off a fishing boat at the Greek island of Lesbos after crossing the Aegean Sea from Turkey in October 2015.
Antonio Masiello/NurPhoto via ZUMA Press
Migrants step over dead bodies while being rescued in the Mediterranean Sea, off the coast of Libya in October 2016. Agence France-Presse photographer Aris Messinis was on a Spanish rescue boat that encountered several crowded migrant boats. Messinis said the rescuers counted 29 dead bodies -- 10 men and 19 women, all between 20 and 30 years old. "I've (seen) in my career a lot of death," he said. "I cover war zones, conflict and everything. I see a lot of death and suffering, but this is something different. Completely different."
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Authorities stand near the body of 2-year-old Alan Kurdi on the shore of Bodrum, Turkey, in September 2015. Alan, his brother and their mother drowned while fleeing Syria. This photo was shared around the world, often with a Turkish hashtag that means "Flotsam of Humanity."
DOGAN NEWS AGENCY/EPA/LANDOV
Migrants board a train at Keleti station in Budapest, Hungary, after the station was reopened in September 2015.
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Children cry as migrants in Greece try to break through a police cordon to cross into Macedonia in August 2015. Thousands of migrants -- most of them fleeing Syria's bitter conflict -- were stranded in a no-man's land on the border.
The Kusadasi Ilgun, a sunken 20-foot boat, lies in waters off the Greek island of Samos in November 2016.
Alexis Malagaris/Samos Divers Association via AP
Migrants bathe outside near a makeshift shelter in an abandoned warehouse in Subotica, Serbia, in January 2017.
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A police officer in Calais, France, tries to prevent migrants from heading for the Channel Tunnel to England in June 2015.
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A migrant walks past a burning shack in the southern part of the "Jungle" migrant camp in Calais, France, in March 2016. Part of the camp was being demolished -- and the inhabitants relocated -- in response to unsanitary conditions at the site.
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Migrants stumble as they cross a river north of Idomeni, Greece, attempting to reach Macedonia on a route that would bypass the border-control fence in March 2016.
In September 2015, an excavator dumps life vests that were previously used by migrants on the Greek island of Lesbos.
The Turkish coast guard helps refugees near Aydin, Turkey, after their boat toppled en route to Greece in January 2016.
Emin Menguarslan/Anadolu Agency/Getty Images
A woman sits with children around a fire at the northern Greek border point of Idomeni in March 2016.
A column of migrants moves along a path between farm fields in Rigonce, Slovenia, in October 2015.
A ship crowded with migrants flips onto its side in May 2016 as an Italian navy ship approaches off the coach of Libya. Passengers had rushed to the port side, a shift in weight that proved too much. Five people died and more than 500 were rescued.
Italian navy via AP Photo
Refugees break through a barbed-wire fence on the Greece-Macedonia border in February 2016, as tensions boiled over regarding new travel restrictions into Europe.
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Policemen try to disperse hundreds of migrants by spraying them with fire extinguishers during a registration procedure in Kos, Greece, in August 2015.
A member of the humanitarian organization Sea-Watch holds a migrant baby who drowned following the capsizing of a boat off Libya in May 2016.
Christian Buttner/EIKON NORD GMBH GERMANY via AP
A migrant in Gevgelija, Macedonia, tries to sneak onto a train bound for Serbia in August 2015.
Migrants, most of them from Eritrea, jump into the Mediterranean from a crowded wooden boat during a rescue operation about 13 miles north of Sabratha, Libya, in August 2016.
Refugees rescued off the Libyan coast get their first sight of Sardinia as they sail in the Mediterranean Sea toward Cagliari, Italy, in September 2015.
Local residents and rescue workers help migrants from the sea after a boat carrying them sank off the island of Rhodes, Greece, in April 2015.
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Investigators in Burgenland, Austria, inspect an abandoned truck that contained the bodies of refugees who died of suffocation in August 2015. The 71 victims -- most likely fleeing war-ravaged Syria -- were 60 men, eight women and three children.