North Korea has reconfigured Japanese-made civilian radar systems for use by naval ships as showcased at an anti-ship missile test reported last year, a document compiled by experts investigating U.N. sanctions against the country says.

The 73-page document, seen by Kyodo News ahead of its submission to the Security Council next month, also cites a ship linked to a U.N.-blacklisted North Korean shipping company berthed near a city in western Japan for a few days last March.

With the revelation that commercial Japanese devices have been funneled to North Korean military forces, the Japanese government may feel compelled to come up with a new response to ensure the effectiveness of sanctions, particularly after its decision Wednesday to tighten measures to punish Pyongyang for its recent activities.