Securities regulators are investigating the firing of a Rodman & Renshaw analyst for allegedly try to write a bearish research report on a company.

The investigation into last May's firing of biotech analyst Matt Murray centers on the analyst's attempt to downgrade shares of

Halozyme

(HTI)

, a investment banking client of the brokerage firm. The investigation by the Securities and Exchange Commission and New York Attorney General Eliot Spitzer was first reported by the New York Post.

An attorney for Rodman Renshaw said "it would be inappropriate'' to comment on what regulators "may or may not be looking at.'' The SEC and Spitzer's office also declined to comment.