Greek police allegedly injured two irregular migrants from Afghanistan as they were trying to cross the border from Turkey to Greece, according to security sources.

The migrants, who were shot by plastic bullets, are currently being treated at a hospital, the sources, who spoke on condition of anonymity due to restrictions on talking to the media, told Anadolu Agency (AA).

With the help of the European Union's border agency Frontex, Greece's conservative government has tightened border controls.

The Greek coastguard said Monday that it takes "all appropriate measures to protect Greece and the EU's maritime borders, respecting international law and human life."

Turkey has repeatedly condemned Greece's illegal practice of pushing back asylum-seekers, stating it violates humanitarian values and international law by endangering the lives of vulnerable migrants, including women and children.

Turkey's five Aegean provinces – Çanakkale, Balıkesir, Izmir, Muğla and Aydın – are prime spots for refugees seeking to leave Turkey for the EU, with Greek islands within sight of the Turkish coast.

In recent years, hundreds of thousands have made short but perilous journeys across the Aegean to reach Northern and Western Europe in search of a better life.

Hundreds of people have died at sea as many boats carrying refugees often sink or capsize. The Turkish Coast Guard Command has rescued thousands of others.

Pushbacks are considered contrary to international refugee protection agreements that say people should not be expelled or returned to a country where their life or safety might be in danger due to their race, religion, nationality, or membership in a social or political group.