A group of two dozen current and former railway employees filed a class-action lawsuit here against Amtrak and many of its labor unions yesterday, alleging that black workers were ridiculed, harassed, and denied jobs, promotions and training.

It's the third such class action filed by black employees against Amtrak. Last month, the court approved an $8 million settlement in another racial discrimination case brought by black managers who had worked at Amtrak. A case also was filed by trackmen in the Northeast corridor.

At a news conference, a group of Amtrak service attendants, conductors, ticket clerks and engineers spoke about their case, some sobbing and others visibly angry. Amtrak employee Mike Helton, a baggage clerk who started at Amtrak in 1989, said one white supervisor frequently made racist jokes and another made racial slurs, but they were not disciplined.

Ken Campbell, the lead plaintiff in the case, said rampant cronyism and nepotism among white railroad workers made the racial problems worse.

"An atmosphere that permits such outrageous and widespread racism in a company of this size, particularly one that is a public carrier and one that receives U.S. government subsidies, is a disgrace," said attorney Warren Kaplan of the Washington Lawyers' Committee for Civil Rights and Urban Affairs, which is representing the workers.

In a statement, Clifford Black, director of public affairs for Amtrak, said the company would not comment on the lawsuit because it has not yet had time to review it.

"Amtrak is committed to diversity and has a zero tolerance for discrimination of any kind in the workplace," Black said. He said Amtrak has made "significant changes" to its personnel policies recently "to ensure fairness, respect and diversity" throughout the company.

Attorneys for the workers said they sued the unions to ensure that improvements in personnel policies would be included in future collective-bargaining agreements.