(Reuters) - Pharmaceutical company Mallinckrodt Plc said on Tuesday it had received a grand jury subpoena from federal prosecutors in Florida seeking documents related to generic drugs it produces that contain the opioid painkiller oxymorphone.

The drugmaker disclosed in a U.S. Securities and Exchange Commission filing that it received a subpoena on Jan. 27 seeking documents related to the company’s distribution, marketing and sale of oxymorphone generic products.

The disclosure came on the same day that the United Kingdom-based company reported earnings. The company reported $792.3 million in net sales in the fourth quarter of 2017, down 4.5 percent.

The subpoena came from the U.S. Attorney’s Office for the Southern District of Florida. Drugmaker Endo International Plc disclosed on Jan. 11 that it received a grand jury subpoena from the same office related to its own oxymorphone products.

Mallinckrodt had no immediate further comment on the subpoena.

There has been a growing number of lawsuits by state and local governments accusing drugmakers including Mallinckrodt of contributing to the national drug addiction epidemic through their marketing and promotion of opioids.

The U.S. Justice Department said on Tuesday it would side with plaintiffs in the litigation as it seeks reimbursement for costs the federal government has borne from the opioid epidemic.

Mallinckrodt in July resolved a federal investigation into allegations that it failed to notify the U.S. Drug Enforcement Administration of suspicious orders of drugs like oxycodone for $35 million.

The drugmaker disclosed in August that it had received a subpoena from the U.S. Justice Department related to its promotional practices and sales involving opioid products including Exalgo and Xartemis XR.

The company says it faces 281 lawsuits seeking damages related to its opioid products and faces investigations by several state attorneys general.