LONDON — Officials from the U.K. have warned of a “highly credible” threat of an attack at Kabul airport by Islamic State militants.It comes as a massive evacuation effort enters its final stages, with countries scrambling to get people out of Taliban-controlled Afghanistan ahead of an Aug. 31 deadline set by President Joe Biden.Some European countries have already begun to halt flights from Hamid Karzai International Airport.The U.S. and other Western countries involved in the evacuation have urged people to stay away from the airport amid growing concerns about possible terrorist activity.The U.K.’s Armed Forces Minister James Heappey told Sky News Thursday that an “imminent, lethal attack” could be about to take place at Kabul airport.“Intelligence over the course of the week has got ever more certain around the highly credible, imminent, lethal attack on the airport or the handling centers being used by western forces,” Heappey told Sky News.The U.K.’s Foreign, Commonwealth and Development Office, meanwhile, issued new guidance to warn of “an ongoing and high threat of terrorist attack.” It urged people not to travel to the airport and move away to a safe location to await further advice.cnbc.com