The al-Jazeera television channel has decided not to broadcast video material it has received that shows the attacks carried out by Toulouse gunman Mohamed Merah.
Officials at the Qatar-based channel announced the decision after a plea by French President Nicolas Sarkozy.
Merah, 23, filmed himself killing seven people, including Jewish children and unarmed soldiers, before he was shot dead after a 32-hour siege last week, the BBC reports.
Police believe the video on a memory stick may have been posted by an accomplice of Merah.
Mr Sarkozy welcomed al-Jazeera's decision and pledged to do all he could to block the transmission of the video should any other media outlet attempt to show it.
Al-Jazeera said it had received numerous requests from media outlets for copies of the video but had rejected them.
The BBC reports says investigators will now try to work out whether Merah passed on the footage via the internet or in person. The original material had been found in his flat after the siege ended and must have been copied.
