The attack unfolded around 6 pm at a home near Balch and Callisch avenues.
Fresno police say a woman and a man who she is friends with had gone to her ex-boyfriend's home to drop some things off.
At some point, officers say the suspect grabbed a shovel and began to hit his ex-girlfriend and her friend with it.
"We do know that some of the neighbors witnessed the disturbance and at least one of them actually intervened to stop the suspect from assaulting the victims," said Fresno Police Lt. Leslie Williams.
After the assault, police say the suspect went back into his home and cut his own arm.
Both victims were taken to the hospital, where the man later died.
Officials say the woman and the suspect, who was also taken to the hospital, are both expected to survive.
Police are now working with neighbors and family members who live in the home to piece together what led up to the assault.
The victims and suspect are said to be in their mid-20s but have not yet been officially identified.
Police say they're unsure if there was a history of violence between the suspect and his ex.
If you are the victim of domestic abuse, or you know someone who is, there is help available 24/7. In Fresno County, call the Marjaree Mason Center at (559) 233-4357. In all other locations, call the National Domestic Violence Hotline at (800) 799-7233.
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