At least some of the intercepts being used in the ongoing investigation into what caused a Russian jetliner's crash in Egypt's Sinai comes from Israeli intelligence sources, CNN reported Sunday. According to a US official briefed on intelligence matters pertaining to the situation, Israeli intelligence sources intercepted communications between ISIS affiliates in Sinai, who have since claimed responsibility for the downing of the plane. Egyptian officials, who are leading the investigation, have been hesitant to comment on the possibility of a bomb on board the plane, although officials told reporters that they still considering "all the scenarios." Israeli officials would not comment on the claims. Lead investigators have stated that they are "90 percent sure" that the noise heard in the final second of a cockpit recording was an explosion caused by a bomb, a member of the investigation team told Reuters on Sunday.The Airbus A321 crashed 23 minutes after taking off from the Sharm al-Sheikh tourist resort eight days ago, killing all 224 passengers and crew. Islamic State militants fighting Egyptian security forces in Sinai said they brought it down."The indications and analysis so far of the sound on the black box indicate it was a bomb," said the Egyptian investigation team member, who asked not to be named due to sensitivities. "We are 90 percent sure it was a bomb."His comments reflect a higher degree of certainty about the cause of the crash than the investigation committee has so far declared in public.Lead investigator Ayman al-Muqaddam announced on Saturday that the plane appeared to have broken up in mid-air while it was being flown on auto-pilot, and that a noise had been heard in the last second of the cockpit recording. But he said it was too soon to draw conclusions about why the plane crashed.British Prime Minister David Cameron said on Friday that it was more likely than not that a bomb brought down the airplane."We cannot be certain that the Russian airliner was brought down by a terrorist bomb, but it looks increasingly likely that that was the case," Cameron said on Thursday before a meeting with Egyptian President Abdel Fattah al-Sisi who is on a visit to Britain.He said Britain had acted before the investigation was complete because the intelligence they had "gave us the concern that it was more likely than not it was a terrorist bomb"."We need to put in place more security at that airport so it's safe to fly people home. That's our priority, that's what we'll work with the Egyptians to do," he said. On Wednesday, a US official said that the latest US intelligence suggests that the crash of Metrojet Flight 9268 was most likely caused by a bomb on the plane planted by ISIS or an ISIS affiliate.