The whereabouts of embattled Texas financier Allen Stanford were a mystery again Friday after the FBI served him a formal complaint in this historic hub noted for ghost stories.

Television crews maintained a vigil outside the family home of a woman reputed to be a girlfriend of Stanford, but there were no signs that he was at the house overnight. Lights were out from early evening.

The modest, three-story, brick-faced townhome belongs to relatives of Andrea Stoelker, according to a cross-referencing data bank and the Free Lance-Star, a Fredericksburg newspaper.

The U.S. Securities and Exchange Commission has accused Stanford of defrauding 50,000 customers around the world in a multibillion-dollar investment scheme.

Acting at the request of the SEC, FBI agents caught up with Stanford on Thursday in Fredericksburg, which lies halfway between Washington and the old Confederate capital in Richmond.

We were helping out there to locate and serve papers, said Bill Carter, an FBI spokesman in Washington. Stanford, 58, was not taken into custody or arrested, he said. Carter declined to say how Stanford had been located.

No one at the Stoelkers' house returned a message left on an answering machine that greeted callers with: You've reached the Stoelkers. We're not available to take your call right now. Please leave a message and we'll call you back as soon as possible.

There were conflicting reports about whether Stanford had surrendered his passport yet. One law enforcement official told Reuters on Thursday that he was making arrangements to do so. ABC News, however, said he had done so Thursday and then driven to Fredericksburg.

Carter referred questions about the passport to the SEC. Kevin Callahan, an SEC spokesman, said he could not immediately clarify the status of Stanford's passport, which a court has ordered him to turn over.

Also uncertain was an ABC News report that Stanford had hired Williams & Connolly partner Brendan Sullivan, one of Washington's best-known criminal defense lawyers, to represent him.

When asked about the ABC report, one of Sullivan's assistants, Rhonda Meadows, told Reuters: Mr. Sullivan has not been retained.

The SEC filed civil charges in Dallas on Tuesday against Stanford and two colleagues, as well as Stanford International Bank Ltd, Stanford Group Co and Stanford Capital Management LLC. The agency accuses them of a massive, ongoing fraud.

Until regulators got help Thursday from the FBI, the SEC could not find Stanford. His whereabouts had been the subject of intense speculation since he failed to respond to an SEC subpoena to answer questions about his company's operations.

Officials did not say how the FBI learned that Stanford was in Virginia, but they said he had not been hiding and he was not a fugitive.

British news reports had identified Andrea Stoelker, a former local resident, as Stanford's girlfriend and president of the board of directors of a cricket tournament that he sponsors in Antigua.

An encounter last November between a Free Lance-Star reader and Stanford seemed to support the idea that his girlfriend has local ties.

The reader e-mailed the paper Thursday night, saying Stanford bought the reader's family dinner at a local restaurant, Claiborne's, on November 7 after the family agreed to give up its earlier reservation time.

He introduced himself as Allen Stanford, said he lived in the Virgin Islands and that his girlfriend's parents lived in the area, the reader wrote.

According to a local tour operator, Fredericksburg has a reputation as one of the most haunted locales in the United States.

With a long history dating back to pre-Colonial times, and a legacy of slavery and war, it is no wonder that so many unhappy phantoms wander the streets, the tour operator says in promotional material.

(Reporting by Jim Wolf; Editing by Lisa Von Ahn)