Police search NSW town for missing teacher

Police divers and the dog unit have spent the day searching a pocket of land and water near Grafton in the state's north for suspected homicide victim Sharon Edwards.

The 55-year-old grandmother and primary school teacher vanished around the Lawrence area, north of Grafton, more than 16 months ago.

Police told AAP they are deliberating whether to continue Tuesday's search west of Lawrence.

The ABC reported investigators were led to the area via a Crime Stoppers tip-off but police would not confirm this.

Mrs Edwards went missing after a night out with friends around Lawrence on March 14 last year.

Her estranged husband, John Edwards, is the main suspect in the case.

He is also the last person to have seen her alive, telling police he saw her at their home in Riverdale Court around 10.30pm on the night she disappeared.

The 58-year-old is on parole after serving three months of a 12-month jail sentence for unrelated firearm offences last year.

Police know Mrs Edwards changed her clothes at her Grafton home and left her car in the garage, but her purse, keys and phone have not been found.