Horry County police are searching for a woman who was last seen in the Little River area on Monday. Crystal Riggins, 37, was last seen around 8 a.m., HCPD says. Horry County police spokesperson Mikayla Moskov says Riggins' absence is unusual, though it's not clear at this point in the investigation if she's in danger or at risk. If you have any information on her whereabouts, you're asked to call 843-248-1520. HCPD says missing woman's absence 'unusual'