Greek police on Wednesday said 39 migrants, including several minors, had been rescued from an islet in Evros river bordering Türkiye.
The group included 13 men, 11 women and 15 minors, the police said in a statement, without disclosing nationalities.
It added that rights activists had alerted the police to their presence.
According to AFP, the migrants were taken to the islet on a dinghy by a smuggler on the Turkish side of the river and left there, the police said.
Athens in 2020 erected a 37.5-kilometre (23-mile) steel barrier in this remote northeastern area after tens of thousands of migrants tried to break through, clashing for days with Greek security forces.
With the country headed into a tight general election later this month, the conservative government has vowed to extend the barrier by another 35 kilometres by the end of the year.
Greece's police minister has said some 265,000 migrants were barred from entering the country illegally last year.
Türkiye and rights groups accuse Greece of pushing asylum seekers back across the border.
Athens denies this, despite numerous testimonies from alleged victims.