MADISON, Wis. -- Madison police have confirmed that one of the four people shot during a domestic dispute during the weekend pulled the trigger.

Friends and neighbors reacted in shock and confusion over Saturday's shooting, which resulted in four people, including two children, being shot early in the morning. The incident occurred in the 1400 block of Loreen Drive on Madison's West Side just after 6 a.m.

Police Sgt. Phil Moore said a 42-year-old woman, 38-year-old man, 7-year-old boy and 8-year-old girl had "various states" of gunshot wounds and were all taken to a local hospital. Moore said one victim ran across the street and called police about 6:20 a.m.

By 11 a.m., crime scene tape surrounded the single-story, A-frame duplex as police officers went in and out of the home.

Moore said they were beginning to emerge from surgery midday Saturday and that some of the victims had stabilized. All lived in a duplex, but the nature of the victims' relationships remained unclear late Saturday night.

"Everybody involved is connected to that specific address," said Moore. "The exact relationship of all the people involved, I don't know exactly."

Police said one of the four was interviewed at the scene, but investigators were still waiting to speak to the other victims in order to make sense of the incident.

Early reports indicated that there was a long history of tension between the couple, although neighbors and friends said they wouldn't have predicted anything close to Saturday’s shooting.

A friend of the 42-year-old woman who would only identify herself as Tiffany, said "This is something that’s going to affect a lot of us for a long time."

Tiffany had praise for the 42-year-old, saying she "is like the sweetest person you could ever know. (The) lady (doesn't) harm to nobody. She (goes) to work, come home, take care of her kids. She (has) tons of grandkids."

Police said that one of the four people shot in the home was also the shooter.

Investigators spent the day combing for clues in and around the ranch-style duplex.

"It makes you wonder what’s happening to the neighborhood," said neighbor Erik Tuhus. "I know it’s the holiday season, and it doesn't discount any other time of year, but it's really sad to hear this time of year, especially when they're a family."

Tuhus and the dozens of others who came by the crime scene on Saturday had just one question: Why?

"This is like a peaceful woman," said Tiffany. "You would never think that something like this would happen to her."

Police said their next step in their investigation will be to interview the people involved, and complete information on how the four were doing following surgery wasn't known late Saturday.

Recovering from surgery will be just the first step in what will undoubtedly be a long healing process for this family.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.