The U.S. Attorney's Office is probing Merck & Co. for allegedly promoting Vioxx, which came off the market in 2004, to medical professionals for purposes unauthorized by the government, The Wall Street Journal reported Friday.

Vioxx was taken off the market after research claimed it was connected to the occurrence of strokes or heart attacks, the newspaper said.

Merck has come up against approximately 27,000 lawsuits initiated by people claiming health damages from Vioxx. A provisional settlement of $4.85 billion was struck by Merck in November, the report said.

"The potential of an indictment can clearly be an incentive for (Merck) to settle civil cases," attorney Joseph L. Doherty told the newspaper.

Merck cited its cooperation with officials in more than 30 investigations into its marketing and sales practices.