A week before Thanksgiving Louisiana government’s computer systems were attached by a “sophisticated and coordinated” cyberattack, according to testimony by a state official. The hackers are believed to live outside the U.S. The attack was similar to one experienced previously by Louisiana school districts and government entities in Florida and Texas.

“This was a criminal act,” Neal Underwood, deputy chief information officer with the Division of Administration, told legislators. “This was not some malcontent teenager in their parent’s basement.”

At a meeting of the legislature’s joint budget committee, Underwood said he didn’t want to compromise the criminal investigation by going into any details. But he mentioned that the hackers used valid credentials to access the state government’s computer network for “a matter of hours.” Staff are investigating how the criminal hackers obtained the credentials.

The type of cyberattack is known as a “ransomware” attack. In this case, perpetrators attempted to lock valid users out of the system and demand payment to let them back in.

State officials say no data was obtained and no ransom was paid.

“We don’t negotiate and respond to ransomware requests,” Underwood said.

Louisiana residents may not realize that state computer systems are attacked thousands of times– every day– he said.

The state’s responded by “wiping away the system that’s been rendered inoperable” and rebuilding the system from its backup and recovery system. The process caused a number of state websites and services to be temporarily unavailable.

About 10 percent of roughly 5,000 state servers and more than 1,500 devices were affected, Underwood said. Older workstations were more likely to be hacked or affected than newer ones were.