PAJU, South Korea — North Korea on Thursday ordered a military takeover of a factory park that had been the last major symbol of cooperation with South Korea, calling Seoul’s earlier suspension of operations at the jointly run facility as punishment for the North’s recent rocket launch a “dangerous declaration of war.”

North Korea said it was responding to Seoul’s shutdown order by immediately deporting the hundreds of South Koreans who work at the complex just across the world’s most heavily armed border in the city of Kaesong, pulling out the tens of thousands of North Korean employees and freezing all South Korean assets. The North also said it was shutting down two crucial cross-border communication hotlines.

Hours after the North’s expulsion deadline, South Korea’s Unification Ministry, which is responsible for ties with the North, said all of the 280 South Korean workers who had been at the facility had finally crossed into South Korea.

The North’s moves significantly raised the stakes in a standoff that began with North Korea’s nuclear test last month, followed by a long-range rocket launch on Sunday that outsiders see as a banned test of ballistic missile technology. South Korea responded Thursday by beginning work to suspend operations at the factory park, one of its harshest possible punishment options.

South Korea said it would ban reporters from the border crossing on Friday.

“I was told not to bring anything but personal goods, so I’ve got nothing but my clothes to take back,” a manager at a South Korean apparel company at the complex, who declined to give his name, told The Associated Press by phone before he crossed to the South.

Chang Beom Kang, who has been running an apparel company in Kaesong since 2009, said from South Korea that his company has about 920 North Korean workers — who didn’t show up on Thursday — and seven South Korean managers at Kaesong.

He said one of his workers, who entered Kaesong earlier Thursday, was about to cross the border to return to South Korea with thousands of women’s clothes produced at the factory. But at the last minute the employee had to drive back to the factory to unload the clothes because of North Korea’s announcement that it would freeze all South Korean assets there.

“I’m devastated now,” Kang said by phone, saying he’s worried about losing credibility with clients because of the crisis.

Yonhap news agency, citing an unidentified military official, reported that South Korea bolstered its military readiness and strength along the western portion of the border in the event of a North Korean provocation. The report didn’t elaborate on what that meant. Seoul’s Defense Ministry would only say that its military has been on high alert since the North’s nuclear test last month.