SIMI VALLEY, Calif. (AP) — The top U.S. officer in the Pacific says Russia reached an agreement with North Korea to send MiG-29 and Su-27 fighter jets to Pyongyang in return for that country sending soldiers to repel Moscow’s invasion in Ukraine.

Admiral Samuel Paparo, commander of the US Indo-Pacific Command, said on December 7 that North Korea provided the soldiers to Russia without a request – the deployment was offered and accepted. The soldiers are not in active combat but are stationed in combat areas, Paparo said.

In addition to the aircraft, North Korea likely wants additional capabilities in return. These could include ballistic missile technologies, particularly re-entry vehicles, as well as new submarine technologies and air defense systems.

Although the aging MiG-29 and Su-27 are not new fifth-generation fighters, they are still “impressive,” Paparo said here at the Reagan National Defense Forum in Simi Valley, California.