[USNBandit]

You have to dig through a couple of links in the source, but it sounds like these guys went into the lav for a prolonged period of time and when confronted they then tried to identify themselves as FAMs. At that point they could not produce credentials. It does not sound like they used fake credentials to get through security with weapons, rather they tried to bluff their way out of the lav issue with the flight crew.

It will be interesting to see how much info on this one comes out.

[USNBandit]

The two gentlemen in question were acting strangely prior to take-off. They were both in the airplane bathroom for quite some time and when confronted by airline personnel they identified themselves as Federal Air Marshals. Neither could produce paperwork confirming this identification and were removed from the plane in handcuffs.

Actually, it is in the source.