A 53-year-old man has been arrested in the North by police investigating the murder of Caroline Graham, who went missing in 1989.
She was 19 and had been living in Portadown when she disappeared. Her body was never found.
Police began fresh searches at her home on Monday.
The PSNI say the man, who was arrested this morning, is being questioned on suspicion of Caroline Graham's murder and possession of a firearm.