WOOLWICH, N.J. – A New Jersey school district is being held hostage for about $124,000 in bitcoins.

Computer hackers took over the Sweedesboro-Woolwich School District’s computer system using “ransomware” last weekend as the district’s four elementary schools prepared to take Common Core-aligned PARCC exams, NJ.com reports.

“Essentially out network has been taken over and made nonoperational,” superintendent Terry Van Zoeren told the news site.

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Hackers sent a message to the district requesting 500 bitcoins, an online currency that equates to about $124,000. As of Tuesday, district officials had not paid the ransom, and were still struggling to regain control of the district’s computer system, though Van Zoeren alleges student data was “not compromised in any way, shape or form,” the Courier-Post reports.

The cyber attack means scheduled online PARCC assessments are delayed, and teachers in the district “are operating as if it’s about 1981 again,” Van Zoeren said.

Aside from student tests, the district’s communications system and school lunch systems are also interrupted. Even teachers’ Excel and PDF files are unusable, NJ.com reports.

“The teachers did a great job of moving forward and picking up the pieces and making sure the kids had a successful instructional day,” Van Zoeren told NJ.com Tuesday.

“The way this ransomware works is different from a lot of viruses you might have heard about or read about,” he said. “A lot of time a virus comes in, attacks a system and destroys it. Ransomware is more like an octopus. It’s tentacles wrap around your data. There’s no destruction or extraction.”

The district’s information technology professionals are working with experts with the Educational Information Resource Center to fix what they can, but it’s a slow process.

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“We are still a long way from being fully operational,” Van Zoeren said. “We have to work to restore the functionality of all our computers.”

The post on the district’s website states that IT workers have restored some files and they’re in the process of trying to remove the ransomware.

“Ransomware is distributed via spam email attachments, applications that are contaminated, or websites that are hacked by criminals,” the district’s website reads, according to NJ.com. “Once discovered, the district took steps to contain the infection and began the process of cleansing and rebuilding.”

School officials contacted police about the breach Tuesday, and were advised not to pay the ransom. Woolwich Township Police are working with the Gloucester County Prosecutor’s Office’s High Tech Crimes Unit, state police, the FBI and Homeland Security to track down the culprits behind the cyber attack.

Technology expert David Suleski, owner of TechStarters, told the Courier-Post “there’s a slip chance (officials are) working with honorable terrorists” and that paying the ransom would likely be a bad idea.

“It’s like a pirate taking a kidnapping victim – they might release the victim for ransom, or they might not,” he said. “They should take a step back and evaluate how this even happened. They should have firewall upon firewall.”

Gloucester County Prosecutor Sean Dalton told NJ.com school hacking incidents aren’t unheard of, but it’s the first time he’s aware of a ransom attempt.

“Certainly any breach of any public computer system, especially a school, is extremely serious and we’re doing everything we can to assist the school district and identify the person or persons responsible,” he said.