(Reuters) - Arkansas’ attorney general on Thursday joined the widening mass of litigation against opioid manufacturers, accusing three drugmakers of promoting addictive painkillers in ways that falsely denied or trivialized their risks.

A Johnson & Johnson building is shown in Irvine, California, U.S., January 24, 2017. REUTERS/Mike Blake

Arkansas Attorney General Leslie Rutledge filed a lawsuit in state court in Little Rock accusing Purdue Pharma LP, Johnson & Johnson and Endo International Plc of engaging in misleading marketing practices.

The case made Arkansas at least the 17th U.S. state to sue manufacturers of prescription opiods amid a nationwide epidemic of addiction to the painkillers.

The lawsuit contended the drugmakers spent millions of dollars on promotional activities that downplayed the risks of addiction associated with opioids while falsely touting the benefits of using the drugs to treat chronic pain.

“The reckless actions of these opioid manufacturers have wreaked havoc upon Arkansas and her citizens for far too long,” Rutledge said in a statement.

Purdue, the manufacturer of OxyContin, denied the allegations in a statement while saying it is “deeply troubled by the prescription and illicit opioid abuse crisis.”

Johnson & Johnson’s Janssen Pharmaceuticals unit - which manufactures drugs including the opioid Duragesic, a form of fentanyl - called its marketing activities “appropriate and responsible.” Endo did not respond to a request for comment.

Prescription opioids are intended to treat pain, but the outbreak of addiction to the drugs has led to a tsunami of lawsuits by cities and counties. The lawsuits have sought to recoup damages from drugmakers for their role in the epidemic.

Opioids were involved in more than 42,000 overdose deaths in 2016, according to the U.S. Centers for Disease Control and Prevention.

At least 433 lawsuits are consolidated before U.S. District Judge Dan Polster in Cleveland, who has been pushing for a quick settlement and has invited state attorneys general with cases and probes not before him to participate in the talks.

Plaintiffs’ lawyers pursuing the case have generally not quantified the potential costs involved in the cases but have compared them with litigation by states against the tobacco industry that led to 1998’s $246 billion settlement.

The U.S. Justice Department in a March 1 filing sought 30 days to evaluate participating in the litigation, citing the “substantial costs that the federal government has borne as a result of the opioid epidemic.”