The U.S. government is trying to force Facebook Inc. to break the encryption in its popular Messenger app so law enforcement may listen to a suspect¡¯s voice conversations in a criminal probe, three people briefed on the case said, resurrecting the issue of whether companies can be compelled to alter their products to enable surveillance.

The previously unreported case in a federal court in California is proceeding under seal, so no filings are publicly available, but the three people said that Facebook is contesting the U.S. Department of Justice¡¯s demand.

The judge in the Messenger case heard arguments Tuesday on a government motion to hold Facebook in contempt of court for refusing to carry out the surveillance request, according to the sources, who spoke on condition of anonymity.