COLUMBIA — Close to 12,500 South Carolina Nationwide Insurance members or policy holders might have had their personal and private information compromised by a breach of the company’s computer network.

The S.C. Department of Insurance announced Wednesday that Nationwide had notified the state that part of the company’s network was criminally attacked on Oct. 3 by an unknown person.

The agency said the breach does not involve the Insurance Department or any other state agency’s system.

Nationwide told the state that Social Security numbers, driver’s license numbers and possibly dates of birth might have been retrieved in the attack. The company is not aware of misuse of personal information at this time, a spokesman said. Nationwide is investigating the incident.

The company is sending written notice to affected customers. The mailings started on Nov. 16.

Nationwide said it is offering affected members free credit monitoring and identity-theft protection services from Equifax for at least one year.

The company has set up a number to answer questions: 1-800-760-1125.