Launceston Police have released the names of the two victims in this week's grisly double murder.

Forensic police are still combing the unit on Pioneer Parade at Ravenswood for clues, after a crime that's left even seasoned investigators horrified.

Fire fighters were called to a Housing Tasmania unit late Wednesday night - on breaking in they found two people who'd been stabbed to death, doused with petrol and set alight.

They've been identified as 21-year-old Joshua Eric Newnman and 31-year-old Angela Maree Hallam.

They were originally from Hobart and Ms Hallam had only moved in recently.

Detectives are following a number of lines of inquiry, but a possible motive remains elusive.