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Russian plane crash: U.S. officials, Egyptian officials disagree on cause

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Handout pictures taken on November 2, 2015 and released on November 3, 2015 by Russia's Emergency Ministry shows Russian emergency services personnel and Egyptian servicemen working at the crash site of a A321 Russian airliner in Wadi al-Zolomat, a mountainous area of Egypt's Sinai Peninsula. Russian airline Kogalymavia's flight 9268 crashed en route from Sharm el-Sheikh to Saint Petersburg on October 31, killing all 224 people on board, the vast majority of them Russian tourists.

Egyptian Civil Aviation Minister Hossam Kamel said officials have found no evidence to support the theory that a bomb caused Russian Metrojet Flight 9268 to crash in Sinai.

At the same time, U.S. intelligence suggests terrorists may have bombed Metrojet Flight 9268. Several countries are taking extra precautions — but for different reasons.

Metrojet’s entire Airbus A321 fleet has been grounded while “additional safety checks are being conducted,” Russia’s federal air safety watchdog Rostransnadzor said Thursday.

But British officials have halted flights from the Egyptian resort city of Sharm el-Sheikh due to concerns that the plane may have been bombed and “a credible threat to British nationals.”

Flight 9268 crashed Saturday in Egypt’s Sinai Peninsula after breaking apart in midair, killing all 224 people on board. It was headed from Sharm el-Sheikh to St. Petersburg, Russia.

U.S. officials told CNN that intelligence suggests ISIS or its affiliates planted a bomb on the Russian plane.

The officials stressed that no formal conclusion has been reached by the U.S. intelligence community and that U.S. officials haven’t seen forensic evidence from the crash investigation.

But the intelligence also suggests someone at the Sharm el-Sheikh airport helped get a bomb onto the plane, one U.S. official said.

“This airport has lax security. It is known for that,” the official said. “But there is intelligence suggesting an assist from someone at the airport. ”

Egyptian authorities, who are leading the investigation into the crash, haven’t publicly responded to reports on U.S. intelligence. Since the crash, they’ve downplayed the possibility that terrorism could be involved.

Why some suspect ISIS involvement

The signs pointing to ISIS, another U.S. official said, are partially based on monitoring of internal messages of the terrorist group. Those messages are separate from public ISIS claims of responsibility, that official said.

In an audio message from ISIS’ Sinai branch that was posted on terror-related social media accounts Wednesday, the organization adamantly insisted that it brought down the flight.

“Find your black boxes and analyze them, give us the results of your investigation and the depth of your expertise and prove we didn’t do it or how it was downed,” the message said. “Die with your rage. We are the ones with God’s blessing who brought it down. And God willing, one day we will reveal how, at the time we desire.”

Doubts about ISIS’ claims

Typically, ISIS is quick to trumpet how and who carried out any attacks for purposes of praise and propaganda. To some, the fact that ISIS hasn’t provided details in this case raises doubt about the group’s repeated claims of responsibility.

Officials in Egypt and Russia have said there’s no evidence to support ISIS’ claims.

“That was a very baffling way to claim credit for what would be the most significant terrorist attack since 9/11,” CNN terrorism analyst Paul Cruickshank said.

“But there may have been a method behind this and a reason behind this, and that may have been to protect an insider at Sharm el-Sheikh airport.”

Foreign tourists stranded in Egypt

Concerns that the plane may have been bombed have left thousands of foreign tourists stuck in Egypt.

British Prime Minister David Cameron’s office said flights scheduled to leave Sharm el-Sheikh for the UK have been delayed as a precaution to allow British aviation experts to assess security arrangements at the city’s airport.

“While the investigation is still ongoing, we cannot say categorically why the Russian jet crashed,” Cameron’s office said Wednesday. “But as more information has come to light, we have become concerned that the plane may well have been brought down by an explosive device.”

An intelligence review revealed “there’s a credible threat to British nationals” — prompting the suspension of flights, British Foreign Secretary Philip Hammond told CNN affiliate ITN.

He said 3,500 British nationals were due to fly out of Sharm el-Sheikh on Thursday.

“We hope by tomorrow (Friday) we will have in place short-term emergency measures that will provide us with the level of assurance we need to allow flights to go out from the UK empty and bring those people back to the UK,” he told ITN.

Tourists stuck at the airport Wednesday vented their frustration.

“People have been shouting at officials,” British tourist Sarah Cotterill told CNN. She was supposed to fly out of the resort city with her sister and their five children.

“We are going to stay in a hotel in Sharm el-Sheikh. I don’t know where. We don’t know anything.”

Ireland has also suspended all flights to and from Sharm el-Sheikh until further notice.

Egyptian Foreign Minister Sameh Shoukry said he was “somewhat surprised” by the British decision.

“I think it is somewhat premature to make declarations related to what might or might not have happened to the aircraft before the investigation is completed and before there is a definitive cause for this crash,” he told CNN.

Militant battleground

Sharm el-Sheikh, where Flight 9268 began its journey, is a beach resort at the southern tip of the Sinai Peninsula. The plane crashed about 300 kilometers (185 miles) farther north, according to Egyptian authorities.

Sinai has been a battleground between ISIS-affiliated militants and Egyptian security forces in recent years. Hundreds have died in the fighting.

ISIS in Sinai is one of the most active of all the ISIS affiliates and has bomb-making capabilities, according to U.S. intelligence. But if the group did plant a bomb on the plane, it would represent an increase in sophistication.

U.S. officials say ISIS has not proved to be nearly as advanced with bomb-making capabilities as al Qaeda in the Arabian Peninsula, a group that U.S. national security officials believed were working on nonmetallic bombs to be smuggled onto planes.

“If ISIS really was responsible for this, this will turbocharge their popularity in the global jihadi movement,” Cruickshank said.

Russia vs. ISIS

If the crash was caused by a bomb planted by ISIS or an affiliate, why might the terrorists target a plane of mostly Russian passengers?

Russia started launching airstrikes in Syria in September, saying it was coordinating with the Syrian regime to combat ISIS and other terrorists.

When news of the crash first broke, an ISIS-affiliated group known as Province of Sinai released a statement claiming responsibility for the crash, saying it had perpetrated the attack “in response to Russian airstrikes that killed hundreds of Muslims on Syrian land,” according to Reuters.

That claim was disputed by officials, who said ISIS couldn’t have fired a missile to bring down the plane.

U.S. officials initially said they doubted Russia’s claims that it was targeting ISIS in Syria. But Col. Steve Warren, a spokesman for the U.S. military’s Operation Inherent Resolve targeting ISIS in Syria and Iraq, said Wednesday that some Russian airstrikes were hitting ISIS targets in Syria.

“They’ve done hundreds of airstrikes at this point. I’m not putting out the count anymore, but they conduct airstrikes, but only a fraction of them have been against (ISIS) targets,” he said. “And when I say fraction, I’m talking … 10%.”

CNN’s Pamela Brown, Elise Labott, Radina Gigova, Lucy Pawle, Sarah Sirgany, Mick Krever, Christiane Amanpour, Margot Haddad, Salma Abdelaziz, Alla Eschenko and Nic Robertson contributed to this report.