The government is investigating trading practices of more than 50 dealers at four New York commodities markets in criminal and civil probes that follow a similar crackdown in Chicago.

The criminal investigation at the sprawling New York trading pits at the World Trade Center reportedly focuses on a firm whose president was cited for regulatory violations in 1985.About 16 agents from the U.S. Postal Inspection Service and the Commodity Futures Trading Commission on Thursday subpoenaed the Commodity Exchange; the Coffee, Sugar and Cocoa Exchange; the New York Cotton Exchange; and the New York Mercantile Exchange. No arrests were made or arrest warrants issued.

The CFTC, a federal regulatory agency, is seeking information about trading practices by firms and individuals in a civil investigation, the exchanges said in statements.

The Manhattan U.S. attorney's office is leading another criminal probe that involved seizing documents from two offices of a single firm, which sources identified as MBF Clearing Corp.

The firm is run by Mark Bradley Fisher, a Comex member who paid $60,000 to settle trading practice violations with the CFTC in 1985.

U.S. Postal Service inspector Jack Ellis said document searches authorized in two warrants were conducted "at two different offices of the same individual" - rooms 992 and 9926 at 4 World Trade Center.

The National Futures Association in Chicago lists the address of MBF Clearing as room 992 of 4 World Trade Center.

Traders said at least three silver futures traders from one company were called off the floor of the Commodity Exchange, while an independent trader was called from the New York Mercantile Exchange.