Growing threat and slaughter from Islamic State group demands formation of a wider coalition between the North African countries and Europe to fight terrorist groups, according to observers.

Egypt's air force bombed Islamic State targets inside Libya on Monday, a day after the group released a video purportedly showing the beheading of 21 Egyptians there.

"The raids definitely will somehow relief the families of the victims, but it's not enough to tackle the serious security situation in the chaotic Libya," said Samir Ghatas, chief of Maqdis Center for Political and Strategic Studies.

The expert expressed "reservation over the strike as it couldn't alone curb the militancy in Libya."

"A comprehensive strategy between the countries harmed from security lax in the neighborhood is necessary," added Ghatas, who is also an expert in the terrorist movements.

There should be an alliance among Egypt, Tunisia and Algeria from one side and Italy, France and the west on the other side, he added.

In Libya there are several Islamist militant groups, but the most influential groups are: Fagr Libya, which hails from Muslim Brotherhood; Ansar al-Sharia, an offshoot of Qaida and the Islamic State or Daesh centered in the Libya eastern city of Derna, Ghatas mentioned.

Militants based in Libya have established ties with Sinai Province, a group operating from Egypt's Sinai Peninsula that has pledged allegiance to Islamic State, he added.

The militants have killed hundreds of Egyptian soldiers and police in Sinai province since the army ouster of the Islamist president Mohamed Morsi in July 2013.

Egypt, the most populous Arab state, has focused mainly on the increasingly complex insurgency within its own borders.

Egypt should shift from the "a negative defense system" over its 1,050 km border with Libya, for safeguarding its national security, to the stage of "creating Mediterranean joint forces."

That alliance should create strategic balances with the tribes in Libya, along with intelligence and launching joint military decisive action there, said Ghatas.

Egypt has not taken part directly in the U.S.-led air strikes against Islamic State targets in Iraq and Syria. However, it called on the U.S.-led coalition to confront militants in Libya on Monday.

"Egypt renews its call for the international coalition to take the necessary measures to confront the terrorist Daesh organization and other similar terrorist organizations on Libyan territories," the foreign ministry said in a statement.

France and Egypt also urged UN Security Council meeting to take new measures against IS.

Meanwhile, Italian Defense Minister, Roberta Pinotti, announced on Sunday that her country is ready to lead an alliance to combat the Jihadist militants in Libya, adding the alliance will be formed of European and North African countries.

"Italy could send thousands of its troops to curb the extremist progress in Libya which became 350 km far from our coasts," Pinotti added.

The 21 Egyptian Coptic Christians, who had gone to Libya in search of jobs, were marched to a beach, forced to kneel and were then beheaded, according to the video, broadcast via a website that supports Islamic State.

Egypt state-run TV said Cairo warplanes struck the group camps, places of gathering and training, and weapons depots in Libya, killing at least 40 suspected IS's Jihadists.

It was the first time Egypt has publically confirmed launching air strikes against the group in neighboring Libya, where extremists groups, threatening both countries, have growing rapidly following the ouster of the Libyan leader Muammar Gaddafi in 2011.

Hossam Sowilam, military expert said that "the air strikes aren't sufficient to eradicate gang wars in Libya."

The raids could only destroy warehouses and camps, but targeting the Islamists masterminds requires long-term strategy.

He added that the war on extremists in Libya would take long time, ruling out that the U.S. would help in combating IS in Libya.

The U.S. forces intensified its efforts in Syria, Iraq and Yemen to defend the oil-rich region, added he.

Sowilam said Egypt couldn't pump its ground forces without neighbor's defense umbrella, to avoid dragging into open fronts abroad, while its internal lines are already under threat of Islamists and branches of the Islamic State.

Muslim Brotherhood in Egypt on Monday blamed the authorities for being reluctant to take hasty actions to release the abducted Egyptians before their slaughter.

The military expert said that beheading the Egyptian Copts came to incite sedition between the Muslims and Copts, make Egyptians lose confidence in the new leadership that ousted the Islamist president Morsi.

The expert agreed with Ghatas that Egypt needs currently to create a trio-alliance with Tunisia and Algeria in coordination with the Libyan Khalifa Haftar's government from one angel, and then penetrate with efficiency the dissent tribes through intelligence channels.