Updated from 10:54 a.m. EDT

Shares in

Lernout & Hauspie


, the Belgian maker of voice recognition software with a large presence in the U.S., plunged in morning trading Thursday after the company said it was being investigated by the

Securities & Exchange Commission

for alleged accounting improprieties.

"The company is cooperating fully in the investigation," the company said in a statement.

The company released the statement shortly after midnight Thursday, and investors were ready to sell at the market open. Lernout & Hauspie finished regular trading down $6.13, or 29%, at $15.13.

The company announced Aug. 13 that it commissioned a company-wide audit in response to allegations raised in

TheStreet Recommends

The Wall Street Journal

. "At this time we have not yet received the results of this comprehensive audit, but we look forward to its completion at the earliest possible date," said John Duerden, the recently appointed chief executive officer of L&H.

In the report, the


said that although L&H said sales from Korea accounted for more than half of total revenue for the first quarter of this year, some Korean companies that L&H claimed as customers said they did no business with the company.



Herb Greenberg

has also repeatedly raised

concerns about the company's accounting practices.