Updated 5:36 p.m. with additional details from press conference.
Investigators say they've determined that a suburban St. Louis woman killed her two young children and herself in the family's Glendale home.
Friday's announcement followed autopsies and several days of investigation by the St. Louis Area Major Case Squad.
Lt. Tim Fagan said at a news conference that 42-year-old Catherine Murch had a history of mental health issues.
"The family was under some strain," Fagan said. "They were under some financial strain. Again, I'm not sure of the value of getting into exact specifics at this point but again, there was some history there and I think the last couple of weeks, the picture we have is that it was increasingly hard for her and she'd been having a difficult time."
Fagan also said Catherine Murch bought a gun online a few days before the shootings.
"There were some internet searches that were conducted by Catherine in the days leading up to this that were specific to this type of incident which I thinks lends to the fact that not only all the physical evidence that we have, but certainly all the circumstantial evidence that we have just points to one conclusion," Fagan said.
According to Fagan, all of the evidence they have says Mitchel Murch II, Catherine's husband, was not involved in the shooting.
Murch called police Monday saying his wife had killed their two children and herself.
Police found the mother in the kitchen, 10-year-old Mitchell Murch III elsewhere on the first floor and 8-year-old Mary Claire Murch on the second floor of the home in the well-to-do suburb.
Murch said he had been reading when he heard the shots.
Funeral services for the family are scheduled for Saturday.
Follow Bill Raack on Twitter: @billraack
