Tributes have been paid to a young mother who was murdered by her ex-boyfriend while their children were in the flat.
The body of Jennifer Rennie, 26, was found at her flat in Findlay Street, Rosyth at around 8am on Monday by a neighbour.
A short time later the body of Scott Simpson, 41, was discovered in Letham Way, Dalgety Bay.
The family of Ms Rennie paid tribute to her and said: "Jenny was a loving mother, daughter, granddaughter, sister and friend. She was a friend to everyone and will be sorely missed. We are all devastated by what has happened and would now ask to be allowed some privacy to grieve at this sad time."
At a press conference on Tuesday the force said the couple had split up several weeks ago and that both bodies had been found within the properties.
The couple's children a five-year-old girl and a one-year-old boy were at Ms Rennie's flat.
On Tuesday flowers were left in Rosyth with a card which read: "Goodbye beautiful girl".
A spokesman for Fife Constabulary said police are keen to talk to anyone who was in the Findlay Street, Rosyth, area around 1am on Monday and who may have heard any disturbance or saw anyone leaving the area around this time.
Superintendent Gary Flannigan said: "We are dealing with a tragedy for two families."
He said the incident looked to be "entirely self-contained" as police dealt with one death and one murder.
Mr Flannigan, of the Serious Crime Division, said: "Events began with a call to a house in Rosyth, and that led us to the house in Dalgety Bay.
"We are fairly confident we know what we are dealing with."
He added: "There are two children at the centre of this tragedy."
Flowers: Police are investigating two related deaths in Fife
Your report: If you have information on this or any other story, please let us know. You can send information, pictures to email@example.com or call us on 01382 591016.
Feedback: We want your feedback on our site. If you've got questions, spotted an inaccuracy or just want to share some ideas about our news service, please email us on firstname.lastname@example.org.