Syria's extremist Nusra Front group has seized two prominent media activists in the country's north, shutting down their radio station and burning rebel flags in the process.

The opposition radio station, Radio Fresh, says on its social media pages that Raed Fares and Hadi Abdullah were abducted by Nusra, al-Qaida's Syrian affiliate, early Sunday morning in a raid in the town of Kafranbel.

The Syrian Observatory for Human Rights, a Britain-based group that tracks the country's civil war, says Fares, who runs the station, was taken because he had criticized the group.

In January 2014, Islamic State militants sprayed his car with 40 bullets, hospitalizing him for three months, and in December of that year, Nusra detained and beat him for three days.