WITNESSES are helping police reconstruct the final moments of Michelle Beets’s life.Detectives spent yesterday piecing together the hours after Ms Beets finished her shift at Royal North Shore Hospital on Tuesday to the moment she was found dead on the verandah of her Chatswood house about 6.20pm.Results of an autopsy, which would show the type of blade used to kill her, were expected last night.Police cordoned off a toilet block in a nearby park where they found bloodstains, leading them to suspect the killer may have tried to clean himself after the attack.They suspect the killer, described as a man wearing a green hoodie and backpack, may have fled there, but because of a malfunction in a nearby council security camera they could not see any images.Police have lots of footage from other security cameras and they locked down Holland Street again last night so that the dog walkers who disturbed Ms Beets’s killer could go through what they saw and heard.Ms Beets got home late because her car would not start after she stopped to buy groceries.The acting commander of the homicide squad, Detective acting Superintendent Mick Sheehy, said it was too early to tell if Ms Beets had been targeted or if she interrupted a burglary.Superintendent Sheehy said there was no clear evidence that the killer was waiting but there was evidence suggesting that someone had tried to break into the rear of the house.”It is a horrific, gruesome crime but it is far too early to identify whether it be targeted or an unfortunate timing incident,” he said.Superintendent Sheehy also confirmed that Ms Beets’s house alarm had been triggered minutes before she got home.Ms Beets’s partner of 19 years, a Sydney lawyer, David Grant, had given a statement to police about her movements and any associations or conflicts which could have contributed to the murder.Her brother, Marty Beets, said Mr Grant was staying with friends and was too upset to talk: ”He’s in total shock.” Last night Mr Grant was due to identify his partner’s body, which is being held at the Glebe morgue.Yesterday flags flew at half mast at Royal North Shore Hospital, where Ms Beets worked in the emergency department for 25 years. Colleagues were offered counselling.