The beheaded bodies of a Syrian activist opposed to the Takfiri group, ISIL, and his friend were found early Friday in the southern Turkish city of Sanliurfa

The beheaded bodies of a Syrian activist opposed to the Takfiri group, ISIL (so-called Islamic State in Iraq and Levant), and his friend were found early Friday in the southern Turkish city of Sanliurfa, his group told AFP.

Ibrahim Abdul Qader, 20, and his friend Fares Hamadi "were found beheaded at the friend's house this morning," Abu Mohammad, a founder of the "Raqa Is Being Slaughtered Silently" group, said via the Internet.

The group, which documents abuses in areas under ISil control in Syria, accused the Takfiri organisation of the murders on its Facebook page.  

According to Abu Mohammad, both men were from Raqa city, the de facto capital of ISIL in Syria. Hamadi was also in his early 20s.

Abdul Qader had escaped to Turkey a little over a year ago.

Members of the activist group had been killed inside Syria in the past, but this is the first time a member had been killed outside the country, Abu Mohammad added.

Turkey's Dohan news agency reported Friday that "two Syrian journalists were beheaded" in Sanliurfa, and that seven Syrians had been arrested by Turkish police.

Sanliurfa is 55 kilometers from Turkey's border with Syria's Raqa province, a major ISIL stronghold in the country.

Turkey has long been accused by Syrian opposition activists, Kurdish fighters and sometimes even Western partners of allowing ISIL members to slip back and forth across its 911-kilometer frontier with Syria.

Bloody bomb attacks in southern Turkey, including an attack in July that claimed 32 lives in Suruc, have been blamed on ISIL, though the group has never claimed responsibility for the blasts.