Victoria Cherry, 44, of Fulwood, Lancashire, has not been seen since October 2015.
Today, Monday 16 January 2017, officers investigating her disappearance have carried out a search of a property on Toronto Street, Bolton.
Following the search, a 43-year-old man has been arrested on suspicion of murder.
Police are now treating the investigation as a non-body murder and appealing for anyone with information about what may have happened to Victoria to get in touch.
Detective Chief Inspector Terry Crompton, of GMP's Serious Crime Division, said: “My thoughts are with Victoria’s family, who are being offered the support of specialist officers at this incredibly difficult time.
“Clearly, the focus of our investigation has now changed and we remain keen to speak to anyone who may have any information about what has happened to Victoria.
“I am urging anyone who has any knowledge of Victoria’s movements since her disappearance, or any information, no matter how insignificant you feel it may be, to please get in touch.”
Victoria was originally reported missing in October 2016 after her family made attempts to find her but were unable to get hold of her.
Anyone with information is asked to contact police on 0161 856 4711, or the independent charity Crimestoppers, anonymously, on 0800 555 111.