(CBS) — Cases of cyber ransomware are on the rise during the pandemic. Criminals are targeting hospitals and schools, with vulnerable remote learning environments. Federal officials expect that will continue through the 2021 academic year.

Teachers in Huntsville, Alabama are printing their lessons on paper after cyber criminals hit the district with a ransomware attack locking down the computer network. “It’s terrible to see a district with some motivated employees moving forward to then have one more obstacle like this,” says William Tunnell with the Alabama Education Association.

Officials are not revealing how much ransom the hackers demand, but Huntsville is far from alone. School computer systems in Baltimore County and Hartford, Connecticut were also hit this year.

Cyber security expert Scott Schober says municipalities, businesses, and even hospitals are ransomware targets. Criminals often send a fake email to employees with a link. Clicking on it downloads malware and allows the hacker into the network. “And now the cybercriminal works laterally through the computer networks to then find the target machine or machines and then encrypt the data and send them the ransom note,” says Schober.

Some ransom notes demand money to restore access to the computer network. Internet security company SonicWall says cases surged 40 percent this year. The average payment also climbed from a few thousand dollars in 2018 to more than 230-thousand dollars. Schober says, “Usually it’s done with digital currency, crypto currency, bitcoin is the preferred choice so the criminals can remain anonymous.”

Security experts say it’s vital for hospitals and every business to have a strong network backup system to thwart ransomware attacks. In October, the Departments of Justice and Homeland Security warned of coordinated cyber-attacks on the healthcare industry.

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