SAN DIEGO (CBS 8) - The investigation continues Friday into the death of 74-year-old Daisy Hayes, who was found shot to death inside her Tierrasanta home.

As loved ones of 74-year-old murder victim Daisy Hayes show up to her home, longtime friends describe a somber mood. Tom Burk, who lived across the street from the Hayes family for the past 40 years, gave Daisy's daughter a hug Friday morning and a word of support.

"That I love them and if they need anything, let me know," he said.

Along with police patrols, Gabacho Drive was filled with homicide detectives Friday. They fanned out across the community talking to neighbors, and when residents weren't home, they left business cards.

Along with taking pictures of the Hayes home where Daisy was found shot to death on Wednesday night, detectives took samples of the front lawn and asked family members if anything was missing from the house.

Margarita Richards lives next door to the murder scene, and says the past two days have been nerve racking.

"Because we don't know who would do that, who killed her, we don't know," Richards said.

Adjacent to this neighborhood is a canyon where neighbors say strange people are always emerging, and there's another theory.

"There was a car parked out in front of our house for a couple of days, a strange car and some guy said the car broke down and he's going to leave it there and he's going to get it fixed. It's gone," Burk said.

Police confirm Daisy's 77-year-old husband Elmer was in the hospital at the time of the murder, so it's possible she was home alone.

"Personally, I think it was someone from outside the family or outside the thing. Somebody who thought maybe there was an easy hit there or something. I don't know, maybe she drove up and got out of the car and found somebody in the house," Burk said.

Police say they found no signs of a struggle, and the home didn't appear to be broken into. So this murder remains one big mystery.