Two researchers from the National Institutes of Health’s Rocky Mountain Laboratories in Montana have been charged with smuggling vials containing the deactivated mpox virus into the United States and allegedly lying about it to federal officials. According to a criminal complaint unsealed in Detroit federal court, Vincent Munster, 53, chief of the virus ecology section, and Claude Kwe, 38, a research fellow, were stopped at Detroit Metropolitan Airport after arriving from the Republic of Congo, where an mpox outbreak was ongoing. The pair had traveled via Paris and landed in Michigan on January 25.

Federal investigators said that Munster and Kwe brought in a large black case containing 113 vials in Styrofoam coolers. After being questioned by Customs and Border Protection (CBP) officers, the two scientists claimed the case held only diagnostics and testing equipment. However, further inspection and FBI tests revealed that 17 of 20 tested vials contained inactivated mpox virus, one contained inactivated chickenpox virus, and two held human DNA.

The FBI said Munster “adamantly denied” carrying any biological materials. Munster also told investigators that any required documentation was in his laptop, but added, “you don’t need them. I do this all the time,” according to the FBI. The Department of Health and Human Services’ Office of Inspector General said, “Any deliberate effort to conceal and smuggle biological materials into the United States without proper authorization is a breach of the public’s trust and could have placed the public at risk."

Mpox, formerly called monkeypox, causes symptoms like rash and fever and can sometimes lead to serious illness, though most people recover fully. The World Health Organization notes the virus can spread through close contact and, since 2022, has been found to spread via sexual contact, leading to outbreaks in over 70 countries. The Republic of Congo recently ended a two-year outbreak linked to more than 2,000 deaths.

The U.S. Department of Justice announced that Munster and Kwe face charges of conspiracy to smuggle and making false statements to law enforcement, with potential sentences of up to five years in prison if convicted. Both men are scheduled to appear in federal court in Missoula, Montana, on Wednesday. The National Institutes of Health stated it is cooperating with authorities, but declined further comment due to the ongoing investigation.

No motive for bringing the deactivated virus samples was mentioned in the court filings, but both defendants are experienced virologists who have worked extensively on mpox research. The investigation remains active, and further legal developments are expected in the coming weeks.