The Al-Jazeera television network said Sunday it had withdrawn an article posted on its website questioning the authenticity of videos showing the decapitation of two US journalists by Islamist militants.

"Out of consideration for the feelings of the families of the victims, whose sorrow it shares, Al-Jazeera has pulled a report on doubts cast on US social media over the criminal decapitations of journalists James Foley and Steven Sotloff. This report was incorrect," the Doha-based network said in a statement.

The Arabic-language article -- headlined "Were Foley and Sotloff really executed?" -- appeared on the website on Thursday claiming that activists "around the world have been voicing doubts that could almost confirm that the two videos were fake."

The article suggested that the faking of such decapitations could be used to justify further military action against Islamist militants.

Sotloff, 31, was shown being beheaded by Islamic State militants in a video released on Tuesday, two weeks after a similar video of Foley was posted online.

Al-Jazeera reiterated its "condemnation of this heinous crime", stressing its policy of "supporting the freedom of journalists and their protection from harm anywhere in the world."