U.S. and Britain warn people to avoid Kabul airport over "imminent attack" threat

The U.S. and Britain have warned citizens not to go to Kabul's airport, citing a terror threat to the sprawling facility outside of which thousands of desperate people have gathered since the Taliban's retaking of Afghanistan. The U.S. Embassy in Kabul sent out an alert on Wednesday evening advising U.S. citizens in Afghanistan to avoid traveling to the airport, citing an unspecified security threat amid frantic efforts to evacuate Americans and vulnerable Afghans. 

"Because of security threats outside the gates of Kabul airport, we are advising U.S. citizens to avoid traveling to the airport and to avoid airport gates at this time unless you receive individual instructions from a U.S. government representative to do so," the security alert read. "U.S. citizens who are at the Abbey Gate, East Gate, or North Gate now should leave immediately." A U.S. defense official told CBS News national security correspondent David Martin on Thursday that the threat was not to planes taking off or landing, but of an explosive device being detonated outside the airport gates. The same official, and others in Washington, denied reports that evacuation efforts from Kabul — which have been enabled entirely by American forces controlling the Kabul airport — were set to end within 36 hours.