Seen at the BBC, thanks to @actuary21c:
Mr Abdulmutallab went to the bathroom for about 20 minutes before the incident, court documents say.
When he got back to his seat, he said he had an upset stomach and he pulled a blanket over himself, the affidavit continues.
"Passengers then heard popping noises similar to firecrackers, smelled an odour, and some observed Abdulmutallab’s pants, leg and the wall of the airplane on fire," the Department of Justice said in a statement. […]
The explosives were sewn into his underwear in Yemen, ABC reported, for what was supposed to be a suicide attack.
So, is anyone going to keep an eye out for massive TSA orders for hospital gowns? Or, have we reached a point where body-shyness will be done away with, Puppet Masters style?

You mean they frisked that 9 year old blonde girl in front of me in the security line for nothing?