China released three Americans as part of a prisoner swap between the Biden administration and the Chinese government, according to a person familiar with the matter, a rare moment of cooperation between the adversaries.

A statement from the National Security Council said the three Americans — Mark Swidan, Kai Li and John Leung — would be reunited with their families “for the first time in many years.” The three had been designated as wrongfully detained in China, and the U.S. statement said there were no longer any Americans held in the country with that status.

The NSC didn’t mention that the three were exchanged for Chinese citizens detained in the U.S. But a person familiar with the matter, who asked not to be identified discussing non-public information, said they were swapped for an unspecified number of Chinese.

Swidan is a Texas businessman who was on China’s death row for alleged drug trafficking, and Li is a naturalized U.S. citizen who imported solar energy technology. Leung, who is also a Hong Kong permanent resident, was arrested in 2021 and sentenced to life in prison last year on spying charges.