TRENTON, N.J. (AP)  -- New Jersey Gov. Jon Corzine expressed shock Monday at allegations New York Gov. Eliot Spitzer was involved in a prostitution ring.

``These are serious and disturbing accusations that are completely at odds with the man I know,'' Corzine said. They come as a complete shock.''

Corzine and Spitzer, both Democrats, have worked closely together on several matters, including redevelopment at the former World Trade Center site.

They also collaborate on matters involving The Port Authority of New York and New Jersey.

Spitzer apologized to his family and the public on Monday, but did not elaborate on reports that he has been involved in a prostitution ring.

Spitzer's involvement in the ring was caught on a federal wiretap as part of an investigation opened in recent months, according to a law enforcement official who spoke to The Associated Press on condition of anonymity because of the ongoing inquiry.

Spitzer identified in legal papers as ``Client 9,'' met last month with at least one woman in a Washington hotel, the law enforcement official said.

``As the governor said, his actions are a clear violation of his own sense of right and wrong,'' Corzine said. ``He will have to regain credibility not only with his family but with the public.''

Speaking later on MSNBC's ``Hardball'' program, Corzine said Spitzer has ``a tough row ahead of him'' to stay in office.

``But he's a man who has dedicated his life to, I think, doing good things for the people of the state of New York,'' Corzine said. ``He's made a big mistake.''

Spitzer joins other area governors to have run into ethics trouble in recent years.

In 2004, New Jersey Gov. James E. McGreevey resigned after announcing he was gay and had an affair with a male staffer.

Connecticut Gov. John Rowland resigned that same year. He pleaded guilty to conspiracy, admitting he accepted more than $100,000 in vacations and trips to Las Vegas from a state contractor and a jet company that received a tax break.

``I think there have been a lot of breakdowns in public trust in general,'' Corzine said. ``This is not unique.''