Jane Onyanga-Omara

USA TODAY

North Korea on Thursday declared an industrial complex it jointly ran with South Korea a military zone and said it was pulling out all its workers.

It comes after South Korea on Wednesday said it would stop operations at the Kaesong Industrial Complex, just over the North’s border, in response to the recent rocket launch and nuclear weapons test by Pyongyang.

A statement by the North's Committee for the Peaceful Reunification of Korea carried by the official Korean Central News Agency called the move "a dangerous declaration of war" and said the site "operated for the common prosperity for more than a decade."

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North Korea said it would expel South Korean workers from the site and freeze the assets, including equipment and products, of firms there. Pyongyang also said it would cut two communication hotlines with the South once the workers were expelled.

Some 124 South Korean companies employed more than 54,000 North Korean workers at the site, which was the last remaining symbol of reconciliation between Pyongyang and Seoul, the South’s Yonhap news agency reported.

On Thursday, South Korea began pulling its citizens out of the complex as South Korean authorities moved to close it, Yonhap said.

North Korea conducted its fourth nuclear weapons test last month and on Sunday fired a long-range rocket over Japanese airspace in what is widely believed to be a test of a new missile system. Both actions are banned by United Nations resolutions.

South Korea's navy on Thursday said it retrieved what is believed to be debris from the rocket on the ocean floor of the Yellow Sea, west of South Korea, Yonhap reported.

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South Korea said ceasing operations at the complex would stop funds from the park being used to develop nuclear and missile technology.

On Wednesday, the U.S. Senate unanimously passed new sanctions against the North for its violations of international law, targeting Pyongyang’s ability to access the money it needs to develop the weapons.