HOPEWELL, Va. (AP) — Authorities haven’t released any updates about the search for four escaped inmates a day after they were discovered missing from a federal prison’s satellite camp in Virginia.

The Federal Bureau of Prisons says inmates Corey Branch, Tavares Lajuane Graham, Lamonte Rashawn Willis and Kareem Allen Shaw were discovered missing from the Federal Correctional Complex Petersburg’s satellite camp in Hopewell, Virginia, around 1:45 a.m. Saturday.

Officials did not release any details about how the inmates escaped. Officials say the U.S. Marshals Service, the FBI and other law enforcement agencies were notified and an internal investigation has been initiated.

Officials didn’t release any new information about the search Sunday.