Sixteen people who worked for defunct securities firm Joseph Stevens & Co Inc have been indicted over a scheme that netted $6.2 million in unlawful stock commissions, the Manhattan district attorney said on Wednesday.

The charges were brought against 11 stock brokers, three traders and two principals from the firm, District Attorney Robert Morgenthau said at a news conference.

The defendants are accused of operating a racketeering scheme and collecting unlawful commissions.

Morgenthau said the scheme involved 800 victims and about 5,000 trades from 2001 to 2005.

It was a very sophisticated operation, Morgenthau said.

He said that, after the Stevens firm broke up, defendants in the case went on to work at other brokerage firms.

(Reporting by Edith Honan and Martha Graybow; Editing by Derek Caney and Andre Grenon)