Did the Feds Kill the SEC's Stanford Investigation?

There's a tantalizing tidbit at the end of the NYT's Stanford report today:

The current S.E.C. charges stem from an inquiry opened in October 2006 after a routine exam of Stanford Group, according to Stephen J. Korotash, an associate regional director of enforcement with the agency's Fort Worth office.
He said the S.E.C. "stood down" on its investigation at the time at the request of another federal agency, which he declined to name, but resumed the inquiry in December 2008.

How many federal agencies have the ability to kill an SEC investigation? This sounds very much as though it's either the FBI or the CIA. Either way, there might be all manner of drug connections we haven't yet heard about -- after all, Caribbean banks have long been used as centers for laundering drug money.

And what prompted the resumption of the inquiry in December? The exit of Thomas Sjoblom as Stanford's lawyer didn't happen until February, according to Bloomberg. Did the un-named federal agency decide to give the SEC the all-clear to restart its investigation at that point? All very odd.

Incidentally, I don't believe the CNBC report that Stanford was in the US on Tuesday, trying to book a private jet to fly him to Antigua. Stanford's a tax exile: he doesn't spend more than 90 days a year in the US at the best of times. And he has his own fleet of private jets. So the chances that he would find himself on US soil, and in need of a jet, just as the SEC filed the case against him would seem to be slim indeed. If the SEC doesn't know where he is, I reckon there's really no chance he's in the US.