(Adds further details on case, background on other lawsuits)
June 21 (Reuters) - Missouri on Wednesday became the third U.S. state to accuse major drug manufacturers of fraudulently misrepresenting the risks of opioid painkillers now at the center of a national addiction epidemic.
Missouri Attorney General Josh Hawley said his office filed a lawsuit in a state court against Purdue Pharma LP, Johnson & Johnson's Janssen Pharmaceuticals and a unit of Endo International Plc.
The case made Missouri the third state to sue drug manufacturers over their opioid marketing and sales practices. Last week a bipartisan group of state attorneys general announced an investigation.
Purdue, J&J and Endo were previously sued in similar lawsuits by the Ohio and Mississippi attorneys general, who also targeted Teva Pharmaceutical Industries Ltd and Allergan Plc.
A copy of Missouri's lawsuit was not immediately available. A news conference was scheduled in St. Louis for Wednesday morning.
Opioid drugs, including prescription painkillers and heroin, killed more than 33,000 people in the United States in 2015, more than any year on record, according to the U.S. Centers for Disease Control and Prevention.
Janssen said in a statement that it acted appropriately and responsibly, adding that its opioid pain medications were approved by the U.S. Food and Drug Administration and carry mandated warnings about their known risks.
Purdue said it denied the allegations but shared Hawley's concerns about the opioid crisis and was "committed to working collaboratively to find solutions."
Endo did not immediately respond to a request for comment.
Similar lawsuits have been filed by local governments, including two California counties; the cities of Chicago and Dayton, Ohio; three Tennessee district attorneys; and nine New York counties.
The companies have denied wrongdoing and generally say the FDA approved their products as safe and effective and that they carried labels that disclosed their risks. (Reporting by Nate Raymond in Boston; Editing by Chizu Nomiyama and Lisa Von Ahn)