Homicide investigators have been in this Central Fresno neighborhood for the last four and a half hours, sifting through evidence inside the house where the violence happened.
They say there's so much evidence, they haven't even called the coroners yet to pick up the victim.
Their best bet to figure out exactly what happened and why is for the suspect to survive.
Paramedics rushed away from the scene of a murder and attempted suicide carrying the only witness to the crime.
Police say the man in the ambulance shot his girlfriend and killed her, then later shot himself too.
Neighbors say the suspect left the house at around 11 a.m., but then came back and he seemed to be in a hurry.
Neighbor: "He looked very agitated. He was going very rapid. He was running and apparently something was going on."
Investigators aren't sure they know who the woman is, but they are sure she was the suspect's girlfriend.
They think the attack was an argument that exploded way out of control.
Jeff Cardinale, Fresno Police Department: "We believe this was a domestic violence situation, a murder suicide. We're checking to see if there are prior domestic violence cases at this address or between this male and female."
One piece of evidence we know police have is the probable murder weapon, but they won't say what kind of gun it is.
This is the 4th murder in Fresno this year. By the end of February last year, there had already been seven.