Police attended a property in Spalding, on Friday, and found the bodies of a man and a woman.
A 29-year old man and a 46-year-old man also found at the property were arrested and taken into police custody.
Police have confirmed the names those who died in this incident are Spalding woman Karolina Zinkeviciene (30) and Breshnev Ruiters (34) of Winsover Road, in the town.
Detective Inspector Andy McWatt, Senior Investigating Officer, says: “The initial post mortem result indicates Karolina was murdered.
“Breshnev Ruiters also died in this incident and although further forensic examinations are required, we are not looking for anyone else in connection with these deaths.
“We will be making no further comment until the conclusion of inquests for both of these people.”
The two men who were arrested on suspicion of murder have now been released with no further action.