New York Gov. Eliot Spitzer, a corruption-fighting politician once known as "Mr. Clean," apologized publicly to his family on Monday after reports emerged alleging he was a client of a high-priced international prostitution ring.

The New York Times broke the story on Monday afternoon, citing one of the governor's officials.

Eliot Spitzer, shown at a memorial service for fallen firefighters in Albany, N.Y. in October, allegedly met a prostitute in a swanky Washington hotel on the evening before Valentine's Day.
(Mike Groll/Associated Press)

According to sources contacted by the newspaper and separately by CNN and the Associated Press, Spitzer was caught on tape last month during a federal wiretap investigation into the prostitution ring.

Four people have already been charged with running the ring, which federal prosecutors said billed each client up to $5,500 US an hour.

Spitzer, 48, apologized Monday at a news conference in New York City, although he would not specifically say what he was apologizing for, and did not specifically address news of the prostitution ring and his alleged involvement.

"I have acted in a way that violates my obligations to my family. I have acted in a way that violates my or any sense of wrong," the father of three said, with his wife at his side.

"I apologize first and most importantly to my family. I apologize to the public to whom I promised better," Spitzer said.

"I disappointed and failed to live up to the standard that I expected of myself. I must now dedicate some time to regain the trust of my family."

At the end of his remarks, reporters attempted to ask Spitzer whether he would resign, but the governor ignored the questions and strode out of the room.

Conspiracy charges filed

Federal prosecutors in Manhattan filed conspiracy charges last week against the four people, accusing them of running a prostitution ring, called Emperors Club VIP, that had wealthy clients in Europe and the U.S.

According to a 47-page affidavit filed by an F.B.I. agent in a New York City federal court, a client alleged to be Spitzer paid $4,300 in cash to have sex with a "petite, pretty brunette, 5 feet 5 inches, and 105 pounds" named Kristen. The woman was told to take a train to Washington from New York on Feb. 13, and meet the client in the Mayflower, a swanky Washington hotel.

The client would be paying for "everything" — train tickets, taxi fare, room service, mini bar fees, travel time and hotel room fees. Some of the money would be for the current meeting, some for future encounters.

The affidavit only refers to the client as "Client 9," but sources have confirmed to the New York Times and Associated Press that "Client 9" is Spitzer.

The case began as a financial investigation by Internal Revenue Service agents, but was referred to the public corruption unit of the U.S. Attorney's office, authorities said. It was not clear from the authorities whether Spitzer was a target of the investigation from the start, or whether agents came his across his name by chance.

Prosecutors compiled statements from a confidential source and an undercover officer and examined more than 5,000 telephone calls and text messages and more than 6,000 e-mails, as well as bank, travel and hotel records.

'He has to step down'

News of the alleged tryst circled through American political circles quickly on Monday, with Republicans lashing out at Spitzer, a Democrat.

"He has to step down," Republican congressman Peter King, of Long Island, said. "No one will stand with him.

"I never take advantage or gloat over a personal tragedy, however this is different. This is a guy who is so self-righteous, and so unforgiving."

Spitzer, a Harvard and Princeton graduate and the father of three teenage girls, began his first term as governor on Jan. 1, 2007. During his election campaign, he vowed to clean up corruption in Albany, the seat of state government.

Before that, he served for eight years as attorney general of New York. He became a national figure — with Time magazine naming him Crusader of the Year — for his involvement in landmark cases seeking to protect investors and consumers.

In his role as attorney general, he also prosecuted several prostitution rings. In 2004, he took part in an investigation of an escort service in New York City that resulted in the arrest of 18 people on charges of promoting prostitution.

He was best known for his investigations into Wall Street crimes in the wake of the Enron, WorldCom and Adelphia collapses, and was once touted as a possible Democratic contender for the U.S. presidency.

With files from the Associated Press