Today the Russian Federal Security Service confirmed that a terrorist bomb was responsible for the crash and destruction of a Russian passenger jet in the Sinai last month.

2.2 pounds of TNT explosives were used to bring the plane down in what officials are saying was “definitely a terrorist act.” Alexander V. Bortnikov, the head of the Federal Security Service, or F.S.B., told the media today that soon after takeoff an IED exploded, causing the plane to mostly disintegrate in midair. Reports show that “foreign made explosive” was found on what was left for investigators to examine.

The Russian government is offering a $50 million reward for information about the group or individuals who brought the plane down. Officials, however, were hesitant to confirm whether or not they believe or have evidence that ISIS or an ISIS-affiliated group was responsible for the attack. In the immediate wake of the attack, many European airlines suspended all travel over the Hassana area in the Sinai where the wreckage was found. The area has played host to clashes between Egyptian forces and a group of Islamic militants who recently pledged their loyalty to the Islamic State.

Airlines are still operating with an abundance of caution, and many are still refusing to fly into the popular Red Sea resort area the Russian jet had taken off from until security improves.

More from CNN:

CNN spoke Tuesday with Carolyn McCall, chief executive of the UK budget airline EasyJet, who has called for aviation security and regulation to be improved.

“The reason the British government advised all airlines to stop flying to Sharm is that they believed there was a device in the hold of the Metrojet aircraft,” McCall said. “They had inside intelligence giving them that information, so that’s not surprising to anybody in the airline industry, given that the British government took very strong action immediately. Clearly, that is why security has got to be enhanced at Sharm el-Sheikh.”

She said EasyJet had suspended flights to Sharm el-Sheikh through the end of this month, as have all other British airlines.

“We will not resume flying until we are told unequivocally by the government that it is safe to operate at Sharm el-Sheikh airport,” she said.

Russia has intensified its attacks against ISIS strongholds in Raqqa and possibly other yet-unconfirmed targets in Syria.

From the New York Times:

Russia struck Raqqa with advanced Kalibr cruise missiles launched from a submarine in the eastern Mediterranean, the RBC news agency reported, citing sources in the Russian Defense Ministry. The agency said it was the first time Russia had fired cruise missiles from a submarine during a war.

There were also news agency reports of Russian fighter-bombers hitting Islamic State targets in Syria, but those could not be confirmed.

The strike came after President Vladimir V. Putin ordered an intensification of attacks following Russian confirmation that the crash of the Airbus A321 in Egypt had been caused by a terrorist attack.

In Washington, a Defense Department official, who spoke on the condition of anonymity to discuss another nation’s military strikes, confirmed that the Russians had provided notice before waging “a significant number of strikes in Raqqa” that may have included the use of sea-launched cruise missiles and long-range bombers.

The official said the notice was in accordance with safety protocols that the United States and Russia agreed to in October that are intended to prevent accidents and ensure safe separation during operations in Syria. The United States has not abandoned any operations because of the Russian strikes, the official said.

Keep in mind that this is a departure from Russia’s previous behavior in the region. After Russia began launching their own attacks in Syria, officials confirmed that those strikes were targeting Russian ally Syrian President Bashar al-Assad.

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