Al-Qaida, or one of its affiliates, may use a new liquid explosive in a possible attack in the near future, according to an ABC News report citing two unnamed senior US officials.
According to the report, clothes may be dipped into the liquid explosives, and become explosive themselves once the liquid dries.
This type of "ingenious" explosive is particularly worrying to security agencies because it would be very difficult, perhaps impossible, to detect, the officials warned.
In response, the US Transportation Security Administration (TSA) chief John Pistole released a statement saying, "I am not in a position to discuss any intelligence around this current threat. But, as a general matter TSA screens both passengers and carry-on baggage for metallic and non-metallic prohibited items, including weapons and explosives. To do this, TSA uses the best available imaging technology to safely screen passengers for any concealed items."
The new development is believed to have been created by the Yemen-based al-Qaida affiliate al-Qaida in the Arabian Peninsula (AQAP). Yemen is also home to alleged bomb maker Ibrahim al-Asiri, who is part of a "most wanted" list released by Yemen.
The list was released by Yemen's embassy in Washington that included 25 "most wanted terrorists" it said were planning to carry out operations in its capital Sanaa, and said it was offering a reward for information leading to their capture.
"The Yemeni government has taken all necessary precautions to secure diplomatic facilities, vital installations and strategic assets," the statement said.
Tensions are rising in the Yemen region as drone strike killed four al-Qaida terrorists, and the US asked citizens, and non emergency government officials to leave the country due to serious terrorist attack threats.
Reuters contributed to this report.