The Department of Homeland Security has issued a new warning to airlines about the possibility of explosives hidden in shoes.
The alert is not based on a specific threat, but comes from new chatter. It applies to airlines with direct flights to the US from other countries.
It focuses on explosives that could be hidden in shoes, liquids, and cosmetics.
Officials say the warning was issued out of an abundance of caution.
"The fact that its only chatter does not give me any comfort.”
In 2001, Richard Reid failed to detonate a shoe bomb aboard a flight to the United States, prompting the security checkpoint requirement that passengers take off their shoes.
“The fact that the terrorists are coming back to shoes is also worrisome to me cause it suggests they may have found a way around security measures."
Former Deputy CIA Director Michael Morell says this new threat may be linked to al Qaeda in the Arabian peninsula's number one bomb maker, Ibrahim Al-Asiri.
"If he has found a way to be creative with shoe bombs that's something we need to worry about."
Morell says the United States has not come close to catching Al-Asiri.