Columbia, SC (WOLO)-- The South Carolina Department of Revenue, Governor Nikki Haley, SLED, and the Secret Service announced at a news conference Friday that approximately 3.6 million Social Security numbers and 387,000 credit and debit card numbers were exposed in a cyber attack.

Investigators say they do know the threat came from overseas but stopped short of identifying where specifically.

The Department of Revenue is asking anyone who has filed a tax return in South Carolina since 1998 to call 1-866-578-5422 to determine if your information was affected.

In addition to the number, the Department of Revenue also recommends individuals take additional steps to protect their identity including; regularly reviewed credit reports, place fraud alerts with three credit bureaus, and place a security freeze of financial and credit information with the three credit bureaus.

ABC Columbia News will continue to follow this developing situation.