The US Homeland Security has issued a terror alert on use of thermos on planes, saying terrorists might conceal explosives inside insulated beverage containers. Transportation Security Administration TSA in a statement issued on Thursday said, in the coming days, passengers flying within and to the US may notice additional security measures related to insulated beverage containers. The TSA however clarified that there is no such specific threat and the measure has been adopted as a matter of precaution as the security agencies keep on updating the terror alert.