National security adviser Shin Won-sik says Russia has strengthened the vulnerable air defense system around Pyongyang by providing North Korea with equipment and surface-to-air missiles.

Shin provided the information Friday in an appearance on “SBS News Briefing” when asked what North Korea was receiving in exchange for deploying troops to Russia.

He also said Russia has provided North Korea with satellite technology and other military technologies since last year.

Shin said he suspects Russia has provided the North with economic support as well.