Official: Attempt to blow up U.S.-bound plane thwarted (video).

U.S. and international intelligence agencies have broken up an attempt to blow up a U.S.-bound jetliner, a U.S. counterterrorism official told CNN. This story is rapidly developing. Follow the live blog below for more details.

[Updated at 5:20 p.m. ET] CNN Terrorism Analyst Paul Cruickshank says one of the key things officials will be looking at is the exact make-up of the device and how it may be similar or different to the device used in in the attempted bombing of an airliner in 2009.

Cruickshank said the suspect in the 2009 attempt, dubbed the “underwear bomber” wore the device for a long time as he traveled throughout Africa and it may have become desensitized. Tests on this device may allow officials to learn more about what changes al Qaeda in the Arabian Peninsula may have been made following the failed bombing.

Source: CNN