Three American citizens imprisoned for years by China have been released and are returning to the United States, the White House said Wednesday, announcing a rare diplomatic agreement with Beijing in the final months of the Biden administration.

The State Department announced the release of Mark Swidan, Kai Li and John Leung. A U.S. government official told NBC News the three were exchanged for two Chinese detainees.

Mark Swidan, Kai Li, and John Leung have been released from detention, a spokesperson for the National Security Council said.