Paju, South Korea: South Korea has cut off power and water supplies to a factory park in North Korea, officials said on Friday, a day after the North deported all South Korean workers there and ordered a military takeover of the complex, which had been the last major symbol of cooperation between the rivals.

It is the latest in an escalating standoff over North Korea’s recent rocket launch that Seoul, Washington and their allies view as a banned test of missile technology. The North says its actions on the Kaesong complex were a response to Seoul’s earlier decision to suspend operations as punishment for the launch.

On Thursday night, 280 South Korean workers who had been at the park crossed the border into South Korea, several hours after a deadline set by the North passed. Their departure quashed concerns that some might be held hostage, and lowered the chances that the standoff might lead to violence or miscalculations.

But they weren’t allowed to bring back any finished products and equipment from their factories because the North announced it will freeze all South Korean assets there.

The North also said it was closing an inter-Korean highway linking to Kaesong and shutting down two cross-border communication hotlines.

“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, said 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 Thursday — and seven South Korean managers at Kaesong.

He said one of his workers, who entered Kaesong earlier on 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 on factory assets. “I’m devastated now,” Kang said by phone, saying he’s worried about losing credibility with clients because of the crisis.

Seoul’s Unification Ministry said in a statement on Friday that it had stopped power transmissions to the factory park. Ministry officials said the suspension subsequently led to a halt of water supplies to Kaesong.

Unification Minister Hong Yong-pyo said the North Korean action was “very regrettable”, and warned the North not to damage South Korean assets in Kaesong.

The South Korean government said on Friday it would extend loans, provide low-interest loans, and defer taxes and utility bills for the companies forced out of Kaesong. Many of the companies now have to find new jobs for their Kaesong employees and build new production lines so they can keep supplying their buyers.

The current standoff flared after North Korea carried out a nuclear test last month, followed by the long-range rocket launch on Sunday that came after Seoul had warned of serious consequences.

In one of its harshest possible punishment options, South Korea on Thursday began work to suspend operations at the factory park. Seoul said its decision on Kaesong was an effort to stop North Korea from using hard currency earned from the park to pay for its nuclear and missile programmes.

The North’s reaction was swift.

The country’s Committee for the Peaceful Reunification of Korea said in a statement later the same day that the South’s shutdown of Kaesong was a “dangerous declaration of war” and a “declaration of an end to the last lifeline of North-South relations.”

Such over-the-top rhetoric is typical of the North’s propaganda, but the country appeared to be backing up its language with its strong response.

The statement included crude insults against South Korean President Park Geun-hye, saying she masterminded the shutdown and calling her a “confrontational wicked woman”, who lives upon “the groin of her American boss.” Such sexist language is also typical of North Korean propaganda.

North Korea has previously cut off cross-border communication channels in times of tension with South Korea, but they were later restored after animosities eased.

North Korea, in a fit of anger over US-South Korean military drills, pulled its workers from Kaesong for about five months in 2013. But, generally, the complex has been seen as above the constant squabbling and occasional bloodshed between the rival Koreas, one of the last few bright spots in a relationship more often marked by threats of war.

Park, the South Korean president, has now done something her conservative predecessor resisted, even after two attacks blamed on North Korea killed 50 South Koreans in 2010. She has shown a willingness to take quick action when provoked by the North. When North Korea conducted its fourth nuclear test last month, for instance, she resumed anti-Pyongyang propaganda from loudspeakers along the border, despite what Seoul says was an exchange of cross-border artillery fire the last time she used the speakers.