Thousands of letters sent out by the S.C. Department of Revenue informing taxpayers their information was hacked began arriving in the Lowcountry this week.

The state has mailed letters to more than 600,000 state residents and 760,000 non-residents informing them that their data was stolen in last year’s massive breach.

The letters were being issued in order of postal ZIP code, from lowest to highest, which put the Charleston-area lower down the list.

“We are writing you today, first to confirm that — as an electronic tax filer — your tax information was compromised and second, to encourage you to take immediate steps to protect yourself against identity theft,” the second sentence of the one-page form letter states.

If you do not receive such a letter, it is likely that your data was not hacked, officials said earlier.

The breach, announced in October, resulted in the theft of records of 3.8 million individual taxpayers, 1.9 million dependents, 699,900 businesses, 3.3 million bank accounts and 5,000 now-expired credit card numbers.

It is the largest known breach of a state agency in U.S. history.