The Islamic State (ISIS) jihadist group has apparently begun a "new chapter" in their campaign of global terror by creating mayhem in the sky following its apparent success in destroying a Russian airliner in mid-air, killing all 224 passengers on board over the Sinai peninsula last Oct. 31.

Rep. Michael McCaul, a US security expert, warned on Sunday that the success of their Russian mission could embolden ISIS terrorists to begin targeting other commercial airliners using various means that may not all be detected and stopped.

The terrorists could even attempt a 9/11-style attack on Britain or America, McCaul said, according to the Daily Express.

The American lawmaker said ISIS has apparently overtaken al-Qaeda as the "premier bomb maker" in the Middle East, no thanks to Western leaders whose "weakness" has emboldened the militants.

McCaul made his remarks following disclosure that British ISIS bomb experts could have made the explosive device that brought down Metrojet flight 9268.

Britain's GCHQ, the government's secret listening centre, earlier picked up "chatter" in Egypt immediately after the Russian plane crash which included voices of terrorist conspirators with London and Birmingham accents.

The British government has already suspended all flights in and out of the resort city of Sharm el-Sheikh in Sinai, Egypt, amid fears of another terror attack on a commercial airliner.

The ISIS has claimed responsibility for the tragedy, even gloating about it in video footage, and saying this was in response to Russian President Vladimir Putin's decision to join the fight against ISIS in Syria.

McCaul, who sits on the influential Homeland Security Committee in the US House of Representatives, said he is "greatly concerned" that ISIS will look to target airliners carrying passengers from other nations carrying out airstrikes including Britain and the U.S.

"All indicators are pointing to the fact this was ISIS putting a bomb on an airplane. I've a high degree of confidence it was," he said during a Fox News TV appearance. "I must say this is a new chapter to ISIS. Typically we looked at al Qaeda in the Arabian Peninsula as the premier bomb maker, if you will, hitting the aviation sector, their crown jewel, but now you're looking at ISIS now putting bombs on airplanes."

McCaul blasted US President Barack Obama for underestimating ISIS. The Republican lawmaker recalled that Obama even once referred to ISIS as the "JV team"—comparing the terrorist group to a Junior Varsity school sports team.

"The sad fact is, because of we've had a failed policy and failed leadership, now we're having to rely on Russians and the Iranians to go into Syria to fight and destroy ISIS, and that's kind of where we are today," McCaul said.

"This weakness invites aggression. We have not handled this right. We haven't done anything. We haven't made decisions in the region in terms of a strategy, and when you don't have a strategy, you fail. I think we're seeing this unfold before our very eyes," he added.