Al-Nusra Front, a Syrian radical group, has condemned US-led air strikes as “a war against Islam”.
The al-Qaeda-affiliated group, in an online statement, called upon jihadists around the world to target Western and Arab countries involved, reported BBC Online.
It comes as the US and other nations widened air strikes against Islamic State (IS) fighters in Iraq and Syria.
The Pentagon said jets hit the Syrian city of Raqqa on Saturday as well as IS positions near the Turkish border.
Kurdish fighters have been defending the Kurdish town of Kobane on the Syrian side of the border since an IS advance sent about 140,000 civilians fleeing to Turkey.
The US-led coalition of about 40 countries, including Arab states, has vowed to destroy IS which controls large parts of north-eastern Syria and northern Iraq.
The group's brutal tactics, including mass killings, beheadings, and abductions of members of religious and ethnic minorities, triggered the international intervention.
Despite sharing radical Islamist beliefs, IS and al-Nusra Front have been rivals, recently clashing with each other in Syria.
