Sen. Charles Schumer wants federal help for New York State so it can guard against cyberattacks. 

This summer, ransomware hackers attacked Rockville Centre School District's computer systems, making the district's computer files inaccessible to district employees. 

The district says it was forced to pay the hackers nearly $100,000 to unlock its computer system. 

Superintendent Dr. Christopher Pellettieri says, “They held our data hostage this summer. It's happened in other places as well as and it needs to stop.” 

Hackers have also targeted police departments and hospitals across the country through ransomware.

Ransomware is a type of malware that encrypts or locks a computer's operating system until a ransom is paid. 

To combat the problem, Schumer is calling on Congress to pass legislation that would create teams of cyber experts within the Department of Homeland Security to help local governments prepare for and respond to such attacks. 

Hackers usually target a network by tricking users to enter a password or click on an email attachment that contains a virus. 

“Once a ransomware infects any system, and it starts to infect it and encrypts data, it's virtually impossible to undo that,” says security systems expert Dr. Tino Posillico. 

He says deploying cyber experts from the Department of Homeland Security will be effective.

“They'll have new types of software and antivirus programs that are going to use an intrusion detection and intrusion prevention component into their security systems, and these systems will actually detect a ransomware attack before it actually happens,” he says. 

Rockville Centre school officials say Sen. Schumer's plan will help ward off criminal hackers.