France to boost security measures after hostage killing

French President Francois Hollande Thursday called for reinforcement of security measures in public places and raising of vigilance after the Islamic State (IS) Sunni radical group threatened to attack French citizens and interests and one of its linked group beheaded a French tourist in Algeria.

"Preventive measures against terrorist risks implemented in the country will be strengthened in public places and transport," the president said.

After a security meeting on nationals' safety and risk of terror menaces, Hollande reiterated his determination to carry out airstrikes targeting IS militants in Iraq in a bid "to support Iraqi authorities to weaken Daesh (Arabic name of the IS) and restore stability and security," and to back "Syrian opposition who is fighting the jihadi group", Xinhua reported.

Earlier, Stephane Le Foll, the government's spokesman said French fighter jets had attacked IS targets Thursday morning for the second time after Paris joined the coalition's military operation on Sep 19 to eradicate Islamist militants who controlled major towns in the OPEC member country.

France's fresh military action came after a Frenchman was beheaded by the Jund al-Khilafah or the Caliphate Soldiers, a group linked to IS militants in Iraq and Syria, 24 hours after an ultimatum demanding Paris to stop attacks in Iraq.

The 55-year-old mountain guide was kidnapped by the Islamist cell last Sunday in eastern Algeria, after IS urged followers to kill Americans and French people and attack nations that have joined a coalition to fight the jihadi group.

Denouncing "the barbaric execution" of Herve Gourdel, Hollande stressed "this crime must not go unpunished", adding "national unity is imperative" to fight terrorism.

Furthermore, the head of state said France "is ready to provide support to all states, at their request to allow the rapid implementation of the necessary measures to strengthen the coherence of international action against the foreign fighters".

Paris has already increased the terror alert to red level after its military operation in Mali, in 2013, ignited terror threats against French interests from the Al Qaeda North African wing (AQIM).

Earlier Thursday, Hollande announced a three-day period of national mourning after the killing of Gourdel.

Flags will fly at half-mast on every public building across the country from Friday to Sunday, Hollande said at a weekly cabinet meeting.

"Herve Gordel was killed because he was French. Facing this important and serious terror threat, determination, sangfroid and vigilance to protect French expatriates and citizens are required, " Hollande said before meeting his military advisors and concerned ministers on French airstrikes against IS positions and terrorism threats.