Data from Seoul point to over 150 cases of illegal exports of strategic items by South Korea that can be used to produce weapons.

South Korea’s trade ministry had compiled a report on the number of such cases last October and another this May, following requests by parliament.

The reports found 156 cases during the four years ending this March.

They included shipments of hydrogen fluoride, which can be used in chemical weapons, to the United Arab Emirates and Vietnam.

The ministry said Wednesday that the shipments did not include hydrogen fluoride produced in Japan.

The Japanese government has stepped up export controls on some high-tech materials to South Korea. It says it found multiple cases of improper trade control in South Korea for the materials, even though they can be used for military purposes. Tokyo says South Korea’s trade control system is insufficient and cites national security concerns in taking the action.

A South Korean expert said the illegal export cases included substances necessary to make the highly toxic VX and sarin gases. The former was used in the murder of Kim Jong Nam, the half-brother of North Korean leader Kim Jong Un.

South Korean government sources say in most cases, smaller firms failed to take necessary steps, not knowing the items were strategic goods.

The trade ministry said it has not found that the items were illegally exported to countries targeted by UN sanctions resolutions, including North Korea.

The ministry claims the documents show South Korea has been cracking down on illegal practices under its export control system on strategic goods.

But the Japanese government is sticking to its claim that it adopted stricter export controls for South Korea because it finds Seoul’s trade management practices lax.