A court in the Greek town of Orestiada on Saturday said it accepted that the pair, a 33-year-old woman and a 31-year-old man, had not known that they had entered a restricted military zone on the Greek-Turkish border.

The journalists had been reporting on a group of migrants for the German public broadcaster NDR, which is part of the national ARD network.

Their lawyer, Dimitrios Kadoglou, told the DPA news agency that the court accepted that at least one no-entry sign had been knocked over and was difficult to see. "They are free again and they can go," Kadoglou said.

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According to the German Embassy in Athens, such instances are common in the area, which is not completely surrounded by a fence or heavily signed. Even locals have been known to unwittingly wander into the zone.

While the area is understood to be heavily policed, journalists who have entered it in the past have usually been released pending trial.

The journalists were taken into custody near the border town of Didimoticho on Friday evening.

According to Greek media, the two had been following a group of migrants who were stranded on a small island in the Evros River, where they had been abandoned by people smugglers. However, this could not be officially confirmed.

NDR said the pair had been working on a report for the current affairs show Panorama.

Migrants and refugees have tried to cross the Evros River in large numbers in recent years, many hoping to travel on to northern Europe.

Read more: In Greece, Turks tell of lives full of fear in Recep Tayyip Erdogan's Turkey

Tensions have increased along the border recently, with two Greek soldiers arrested nearby last week after crossing the border into Turkey.

The soldiers, who are to stand trial, said they lost their way during poor weather, but Turkey has accused them of espionage. Athens accuses Ankara of seeking to use the soldiers as bargaining chips as it seeks the extradition of eight soldiers from Greece in connection with the failed Turkish coup attempt of 2016.

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rc/sms (AFP, dpa, EPD)