Two top naval intelligence officers have been placed on leave and stripped of their access to classified materials in a widespread bribery investigation, the Navy said Friday night.

The sanctions against Vice Adm. Ted Branch, the director of naval intelligence, and Rear Adm. Bruce Loveless, the director of intelligence operations, are related to “illegal and improper relations” with Leonard Francis, chief executive of Glenn Defense Marine, a Singapore-based defense contractor, the Navy said in a statement.

The admirals are the highest-ranking officers to be implicated so far in the investigation, which began in 2010. Three lower-level officers have been charged with accepting prostitutes, luxury travel and cash from Francis in exchange for classified and internal Navy information.

Francis appeared in federal court Friday in San Diego on allegations that he supplied the lower-level officers — Cmdr. Mark Vannak Khem Misiewicz, 46, Cmdr. Jose Luis Sanchez, 41, and Naval Criminal Investigative Service Supervisory Special Agent John Bertrand Beliveau II, 44 — with plane tickets, access to prostitutes and concert tickets.