Russian investigators, as well as Egyptian President Egyptian President Abdel Fattah el-Sisi, dismissed these claims, and experts said the plane was flying at an altitude too high for a missile to reach it from the ground.
Earlier Wednesday, Downing Street announced it would temporarily delay United Kingdom-bound flights scheduled to depart the Sharm el-Sheikh airport, where Metrojet Flight 9268 took off, citing concerns over terrorism, the BBC reported. Prime Minister David Cameron’s office said a team of British aviation experts would travel to the Egyptian airport, where they will “make an assessment of the security arrangements in place” and “identify whether any further action is required.”
“While the investigation is still ongoing we cannot say categorically why the Russian jet crashed,” the statement read. “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.”
The office did not elaborate on what that new information may be. Cameron is scheduled to meet with el-Sisi on Thursday, whom he called Tuesday night to “discuss what measures the Egyptians are taking to ensure the tightest possible security arrangements at Sharm el-Sheikh airport,” according to the statement.
Also on Wednesday, the Irish Aviation Authority, a state-owned air safety regulator, directed Irish airlines not to fly to or from the airport in Sharm-el-Sheikh or in Sinai airspace, the BBC reported.
A top Egyptian aviation official told the AP that Russian and British airlines checked out the airport’s security procedures on Wednesday and “left without making a single remark about it.” Egyptian officials say the airport is safe.
James Clapper, the U.S. Director of National Intelligence, said Monday that Islamic State involvement in the crash was “unlikely, but I wouldn’t rule it out.” A U.S. official told CNN Tuesday that a U.S. military satellite had detected a heat flash in the sky over the Sinai that officials attributed to the Russian plane. The presence of a heat flash suggests that there was “a catastrophic in-flight event,” but that could be a number of things, including explosions from malfunctioning engines or bombs.
Several international airline companies changed their flight procedures shortly after the crash. Lufthansa and Air France-KLM said Saturday they would avoid flying over the Sinai Peninsula until investigators determined a cause. Emirates airlines followed on Sunday, saying it would stop flying over the peninsula “until more information is available.”
The White House said Wednesday afternoon that the Federal Aviation Administration had previously notified U.S. aircraft about flying over the Sinai. The U.S. has not made any aviation policy changes in response to the crash, and U.S. airlines do not operate flights between the Sharm el-Sheikh airport and any locations in the U.S.
Russian officials on Wednesday expanded the search area of the debris site of the jetliner, which crashed early Saturday morning about 23 minutes after takeoff. Most of the passengers were Russian. All perished.