North Korea appears to have operated South Korean facilities at the Kaesong Industrial Complex without permission, South Korea’s Unification Ministry said Tuesday.

The Unification Ministry has found indications that the North Korean authorities have operated the factories built and owned by South Korean companies at the inter-Korean industrial park in North Korea, an official -- who wished to remain anonymous -- said during a closed-door briefing.

“We have recently detected related signs, including the movement of North Korean vehicles and supplies piled up at the industrial complex, through various channels,” the official said, without further details.

The Unification Ministry has observed unidentified vehicles moving around the Kaesong Industrial Complex several times since April when a fire was detected in the area.

“Therefore, North Korea appears to have been operating some of our factories at the Kaesong Industrial Complex when we piece the situation together,” the official explained.

The Unification Ministry also sees that North Korean workers have been manufacturing items at South Korean factories located in the North Korean border city of Kaesong, according to the official.

The South Korean government has said South Korean companies have the ownership of factories, machinery and equipment that were left at the industrial park which was jointly run by the two Koreas.

The Park Geun-hye government suspended the operation of the Kaesong Industrial Complex in Feb. 2016 in response to North Korea’s nuclear testing and the test launch of the Kwangmyongsong-4 satellite. At that time, the government said the majority of North Korean workers’ wage income at the Kaesong Industrial Complex was funneled into the North Korean regime.

The Unification Ministry’s confirmation came a day after its spokesperson Cho Joong-hoon publicly condemned North Korea for violating the property rights of South Korean people, including the unauthorized use of shuttle buses, during a regular press briefing.

For instance, a commuter bus -- which are believed to have been produced by South Korea’s Hyundai company and used to convey North Korean workers from and to the Kaesong Industrial Complex -- were seen operating in the city of Kaesong in the video footage aired on July 3 by the state-run Korean Central Television.

North Korea also has been demolishing South Korean-built facilities at the Mount Kumgang resort since this March without prior consultation with the South Korean government.

“The government continues to keep close tabs on North Korea’s moves to tear down or use our facilities at Mount Kumgang and the Kaesong Industrial Complex without permission,” Cho said Monday.

“North Korea’s act clearly violates the inter-Korean agreement, and we express our regret at the illegal infringement of our property rights. North Korea must immediately stop the act, and we make it clear that all responsibility lies with North Korea.”

The two Koreas commit not to nationalize or expropriate investment assets of the other side and place restrictions on property rights in the Inter-Korean Agreement on Investment Protection signed in December 2000.

(dagyumji@heraldcorp.com)