The United States has issued a terror alert warning airlines of possible attempts to attack passenger jets using explosives packed in shoes.
The Department of Homeland Security issued a bulletin but its warning was not specific to an airline, or time frame.
The department suggested flights from overseas, coming into the U.S., are potentially at risk, not domestic flights within the United States, Fox News reports.
According to the report, it called on screeners to increase their use of explosive detection swabs on passengers' shoes.
