A 59-year-old woman was found dead by her sister at her home in Cornacully Road between Belcoo and Garrison, at about 1pm on Tuesday, November 13.
Pauline Kilkenny had been working at Lilleys Centra on the Shore Road in Enniskillen for the last two years.
A 28-year-old man has been arrested on suspicion of murder.
He is also being held on suspicion of possession of cannabis and theft of a motor vehicle.
It is understood Ms Kilkenny did not show up for work on Monday having taken a few days off at the end of last week.
Detective Chief Inspector PSNI John Caldwell said, "A post-mortem examination has yet to take place but I am treating this as murder. My thoughts go out to the victim's family, including her sister who will no doubt have been left traumatised by the discovery of her sister's body."
He said the contents of the victim's handbag and her car had also been removed from the property.
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