Senior al Qaeda leader Sheikh Harith al-Nadhari released a recording over social media websites on Friday, denouncing the "filthy" French and calling them "the heads of infidelity who insult the prophets."

Referring to the attack on satirical magazine Charlie Hebdo, he said it would be "better for you [the French] to stop striking Muslims so you can live in peace. But if you only wish for war, then rejoice, you will not enjoy peace as long as you wage war on God and his prophets and fight Muslims."

The terrorist leader said that the attackers were a group of "the faithful soldiers of God," but stopped short of claiming responsibility.

In a TV interview on Friday evening, French Prime Minister Manuel Valls said authorities were bracing for possible further attacks.

"We are facing a major challenge" and "very determined individuals," Valls said.

On Wednesday, three men entered the Charlie Hebdo offices in central Paris, killing 12 people. French police subsequently launched a massive hunt for those responsible.

On Friday, three suspects surfaced and took a print shop and a kosher supermarket hostage for several hours before police raided the premises, killing the men and a number of hostages.

Following Friday's events, the death toll has climbed to 17.

Al Qaeda financed gunman

Before being shot dead by police forces, one of the attackers in the Charlie Hebdo massacre, Cherif Kouachi, admitted he was financed by al Qaeda of Yemen.

French television channel BFM TV aired a phone conversation with Kouachi, who said his trip to Yemen was financed by American-Yemeni cleric Anwar al-Awlaki, who has been linked to al Qaeda. Al-Awlaki was killed in a drone strike in September 2011.

Earlier Friday, French President Francois Hollande denounced the attacks in an address to the nation. "These madmen, fanatics, have nothing to do with the Muslim religion. France has not seen the end of the threats it faces," he said.

The French government was planning a march of national unity on Sunday in Paris. Hundreds of thousands are expected to attend, including German Chancellor Angela Merkel, UK Prime Minister David Cameron and Italian Prime Minister Matteo Renzi.

mg/cmk (AFP, AP, Reuters)