The bodies of two French journalists shot dead in the rebel-infested northern desert of Mali arrived home in Paris early Tuesday, as Bamako vowed to hunt down their killers.

The Air France flight carrying the coffins of of Ghislaine Dupont, 57, and Claude Verlon, 55, arrived at the Charles de Gaulle airport in the French capital from Bamako.

Lawyers on Monday challenged a decision to extradite a Lebanese-Canadian university professor accused of a deadly 1980 bombing of a Paris synagogue, calling France's key handwriting evidence "fatally flawed."

Hassan Diab is appealing a 2011 court decision and the Canadian government's order to extradite the University of Ottawa sociologist to France, despite the court's concerns that the case was "weak."

Hundreds of Malian reporters marched through the capital Bamako on Monday in silent tribute to two French journalists shot dead by suspected terrorists in the country's north.

A management team from Radio France Internationale (RFI), where Ghislaine Dupont and Claude Verlon had worked for many years, took part in the march as they made preparations for the repatriation of their colleagues' bodies.

An international operation was under way on Monday to hunt the killers of two French journalists shot dead in Mali, with a police source in the country's north saying around a dozen suspects had been arrested.

Ghislaine Dupont, 57, and Claude Verlon, 55, were kidnapped and killed by what French Foreign Minister Laurent Fabius said were "terrorist groups" in the flashpoint northeastern town of Kidal on Saturday.

Paris on Sunday blamed terrorist groups for the murder in "cold blood" of two radio journalists in northern Mali, and said French troops would boost security in the restive zone.

Foreign Minister Laurent Fabius said Radio France Internationale (RFI) journalist Ghislaine Dupont and sound technician Claude Verlon were shot dead after being abducted by armed men on Saturday.

The United Nations Security Council has "strongly condemned" the kidnapping and slaying of two French radio journalists in Mali's troubled northeast.

The journalists -- Ghislaine Dupont and Claude Verlon of Radio France International (RFI) -- were found dead after being kidnapped by armed men in the northern city of Kidal.

Egyptian authorities Saturday launched a nationwide search for a French woman reported missing when she failed to catch a connecting flight the day after she arrived in Cairo, officials told Agence France Presse.

The 25-year-old arrived in Cairo from Ghana on Thursday evening and had been due to fly to Basel-Mulhouse airport in France on Friday, airport security officials said.

Spy agencies in Germany, France, Spain and Sweden are carrying out mass surveillance of online and phone traffic in collaboration with Britain, according to documents leaked by Edward Snowden, the Guardian newspaper reported Saturday.

Britain's GCHQ electronic eavesdropping center -- which has a close relationship with the United States' National Security Agency (NSA) -- has taken a leading role in helping the other countries work around laws intended to limit spying, the British newspaper said.

A French court on Thursday rejected a detained former Georgian defense minister's plea to be set free but did not rule on his extradition to his homeland, where he is wanted on corruption charges.

Davit Kezerashvili, a close ally of outgoing president Mikheil Saakashvili, was detained on October 14 at Nice airport following an international arrest warrant.

France on Wednesday slammed as "unlikely" U.S. allegations that European spy agencies shared phone call records with U.S. intelligence, as a transatlantic surveillance row intensified.

General Keith Alexander, head of the U.S. National Security Agency, on Tuesday took onlookers at a Congress hearing by surprise when he dismissed allegations that his agency had swept up data on millions of phone calls in Europe as "completely false".