CHERRY HILL - The township school district on Tuesday entered its sixth day of an incident that's knocked out parts of its computer system.

The outage began Thursday night with an inability to send or receive emails, according to a statement posted to the district's website.

The extent of any additional problems was not immediately known.

However, some files within the computer system were reported to be encrypted and screens displayed the word, "Ryuk," which is associated with a criminal organization that demands ransomware payments to unlock affected computer systems.

Superintendent Joseph Meloche declined to comment on a possible cause for the outage, saying the district was focused on restoring the computer service.

"We're addressing the need to get all of our system back online," said Meloche, who noted the district has brought in outside experts as part of that effort.

Meloche said some affected areas had already been restored, and the district believes the full system could be running by the end of this week.

In its statement, the district said any emails sent since Thursday "have not been received by our staff, teachers and administrators."

"We are not able to send emails via district email accounts," it added, suggesting people call or fax to communicate with school employees.

"Our technology team has been working around-the-clock to resolve the issue since it surfaced on Friday morning," the statement said.

CrowdStrike, a cybersecurity firm, says the Ryuk virus "is specifically used to target "enterprise "environments" for monetary ransoms. It estimates "threat actors" have used the virus to collect more than $3.7 million in ransom since August 2018.

The New Jersey School Boards Association says ransomware attacks "have been a threat for more than a decade, and they continue to increase in volume and level of sophistication."

It is offering an online seminar to members on Tuesday to defend against ransomware attacks.

According to Emisoft, an antivirus firm, at least 62 U.S. school districts and other educational institutions were hit by ransomware attacks in the first nine months of this year.

It noted Louisiana Gov. John Bel Edwards declared a state of emergency after multiple districts were attacked in that state. That allowed state resources, such as cybersecurity experts, to assist the affected schools.

It noted an insurer paid most of an $88,000 ransom for the Rockville Centre district in New York state, while the 16-school Moses Lake district in Washington State rebuilt its computer system to avoid a demand for $1 million after an attack originating from an IP address in Moscow.

All of those attacks occurred in July, said New Zealand-based Emisoft.

Jim Walsh is a free-range reporter who’s been roaming around South Jersey for decades. His interests include crime, the courts, economic development and being first with breaking news. Reach him at jwalsh@gannettnj.com or look for him in traffic.

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