Three migrants were found dead Tuesday on a railway track in northern Greece, apparently killed by a train while asleep, local police said.

The bodies were spotted by the train driver near the village of Fylakio, which lies between the cities of Alexandroupolis and Komotini, near the Greek border with Turkey.

Police said they were unable to immediately identify the victims.

The area lies on a migration route into Greece from Turkey that has been increasingly used by smugglers.

Greece has long been the first destination for illegal immigrants, including Syrians and other Asian migrants, setting out on a journey to Europe via Turkey. Greek authorities have recorded over 14,000 irregular entries across the Turkish border so far this year, compared to some 5,500 in 2017.

The sharp increase in overland arrivals has been accompanied by successive deadly accidents in the north of the country, as illegal networks cram dozens of migrants into cars driven by teenagers.

Over a dozen refugees and migrants have been killed in such accidents in the last two months.

Though it embraced refugees seeking permission to cross into other European countries, particularly Germany, for the past three years, Greece has slowly become an unfavorable place for migrants due to worsening conditions in camps where migrants are held. Along the Turkish border, Greek officials have allegedly engaged in "pushback," an illegal practice that forcibly deports migrants back over the border.

Turkish media outlets say Greece "pushed back" some 4,000 illegal immigrants last year. Based on the accounts of the illegally deported migrants, Greek police officers are accused of confiscating valuable possessions of migrants and torturing them.