The state Department of Health is investigating a potential breach of private medical information of disease test results.

The DOH Disease Outbreak Control Division, which investigates cases that affect public health, detected the suspicious activity last week on its reporting system. The data was compromised and the affected server was removed from its network, the department said.

The Health Department didn’t know how many records may have been affected, but said it is conducting a investigation to “determine the full extent of the compromise and its potential impact.” The department collects data on the mumps, rat lungworm disease and other reportable conditions.

Federal and state law enforcement agencies are involved in the probe.

“Although there is no evidence of data being stolen, the department is acting in an abundance of caution to prevent any possible breach and secure individual data,” Health Director Virginia Pressler said in a news release. “The department is working closely with ETS to ensure safeguards are in place to restore confidence in the system, which is vital to the tracking and controlling of infectious diseases in the state.”