Sinai plane crash an act of terror, claims Russia
Russia has claimed for the first time that a bomb brought down a Russian passenger plane that crashed over Egypt's Sinai Peninsula, killing 224 people.
Isil had already claimed the bombing and the Kremlin launched an immediate attack yesterday, with cruise missiles and bombs striking Raqqa, Isil's self-declared capital in Syria.
However, officials in Cairo say their investigation had yet to find any evidence of criminal action.
Alexander Bortnikov, head of Russia's FSB security service, said traces of foreign-made explosive had been found on fragments of the downed plane and on passengers' personal belongings.
"We can unequivocally say it was a terrorist act," Mr Bortnikov said.
Russian President Vladimir Putin said that Russia would be relentless in hunting down those responsible for the attack.
"There's no statute of limitations for this. We need to know all of their names," Putin said.
"We're going to look for them everywhere, wherever they are hiding. We will find them in any place on Earth and punish them."
The Russian leader said his air campaign in Syria "should not only be continued but should be intensified so that the criminals realise that retribution is inevitable".
"In this work, including the search to find and punish the criminals, we are relying on all of our friends," Putin said.
"We will act in accordance with the UN Charter's Article 51, which gives each country the right to self-defence.
"Everyone who tries to aid the criminals should understand that they will be responsible for giving them shelter."
The FSB offered a $50m (€47m) reward for information leading to the arrest of those responsible, appealing to the "Russian and international communities for cooperation in identifying the terrorists." The FSB specified that the reward would be paid in dollars.
"According to our experts, a homemade explosive device equivalent to 1kg of TNT went off onboard, which caused the plane to break up in the air, which explains why the fuselage was scattered over such a large territory," said Mr Bortnikov.
He added that tests showed the explosives had been produced outside of Russia, but gave no further details.
One US defence official said the Russians gave prior notification of their attacks on Raqqa by communicating with the US-led coalition's air operations centre at al-Udeid air base in Qatar.
All of the people on board, most of them Russian tourists, were killed when the Metrojet Airbus 321-200 crashed over the Sinai Peninsula on October 31, about 23 minutes after taking off from the Red Sea resort city of Sharm el-Sheikh.
The plane was heading to St Petersburg, where most of the passengers were from.
Soon after the crash, Isil claimed responsibility in written statements, as well as video and audio messages posted on the Internet.
It said the attack was retaliation for Russia's air campaign against Isil and other groups in Syria, where Moscow wants to preserve the rule of President Bashar Assad.
Egypt's government held its weekly meeting in Sharm el-Sheikh to show solidarity with a tourism industry hit by cancellations.