SPARTANBURG, S.C. (AP) — The computers of a library system in South Carolina have been hit with a ransom ware demand.

Spartanburg County Librarian Todd Stephens told local media that library users were unable to check out or return books Tuesday because of the attack by cybercriminals. Stephens says a library technician noticed suspicious activity around 11 a.m. Monday.

He said technicians were working on the problem and do not know when the computer network and website will be restored. Stephens says he doesn't know the extent of the damage.

He says the attack has demanded payment 3.6 to 3.8 bitcoin, which he said is about $36,000. Stephens says he doesn't plan to pay the ransom.

He says there is no indication of a data breach.

The library and its 10 branches are open.