They probably cleared customs in Bangor.
************************************************** *****

Bob, this interested me enough to spend 45 minutes on the phone, with 7
different customs offices, finally ending up with a Mr. name withheld
by me for reasons below who explained the procedure...
Federal agencies reentering the country on official business,
especially with prisoners, normally have one or more of those federal
personnel being also a customs agent with the authority to interview
and clear people in and out of the country... So Entwhistle would have
been interviewed and cleared into the country while in the air... Same
for all persons aboard the aircraft... The plane hits the ground, the
prisoner is hustled to the car, and everyone scatters before the
prisoner can meet his just desserts...

I then asked about U.S. war ships, etc., entering and leaving the
country... Same deal, some officers aboard a military ship have customs
agent authority and all the paperwork is completed aboard the vessel
prior to exit or entry...

SCOOP for RAP members only:
He also mentioned that the planes moving prisoners to and from
Guantanamo have a federal agent on board with customs authority who
clears them in and out of the country without going through the customs
gates...
I strongly doubt he intended that for the 6 o'clock news, so I have
chosen to redact his name above... But, it's an interesting tidbit...

Foaming at the mouth media mongors need not call me as I won't discuss
it...

BTW, there is a customs and border agent on board Air Force One and he
interviews and clears everyone, including the President, in and out of
the country... At which point I regaled him with the story reported
here on rec.aviation of Vice President Dan Quail having to remove his
shoes and be patted down at the airport... He laughed, said he both
knows and likes Mr. Quail, but if he were the agent, 'it would have
been down to his skivvies!'

Famous, new saying, copyright to me:
"There is nothing more powerful than a little authority."

Remember that when you are dealing with the TSA agent at the airport,
who was a medicaid momma before she was given 3 weeks of classroom
training, a badge and the power to destroy your life......

denny