Greece’s President Prokopis Pavlopoulos came out swinging against Turkey’s handling of the refugee crisis, claiming in a meeting with his German counterpart that Turkish border authorities are guilty of slave trade.

In a meeting with German President Joachim Gauch, Pavlopoulos said Turkey was aggravating the refugee crisis.

“I have a strong fear that Turkish smugglers have the support of the authorities, in particular, border authorities who act like they have seen nothing,” Pavlopoulos told German newspaper “Süddeutsche Zeitung.”

“There are even cases where the smugglers are helped. We have evidence. It’s a type of slave trade,” the president said, adding that “These illegal economic migrants, who arrive in Greece because Turkish authorities are not doing their work, should be sent back to Turkey under the accords in force.”