The shooting happened in northeast Harris County in the 11700 block of S. Spicewood Lane around 11 p.m. on Thursday.
A woman and her boyfriend were fighting. Harris County Sheriff's Office said during the argument that the woman took her two children to the home next door where three brothers lived for safety reasons.
Police said they did not know how well the men knew the woman but were told that the woman felt safe enough to go there for help.
The woman's boyfriend then came over, where he was confronted by the three brothers outside.
Police said that is when the boyfriend reportedly pulled out a gun and fatally shot two of the brothers.
One of the brothers also pulled out a weapon and shot back at the boyfriend, who ran back to his home.
HCSO said that shortly after, the woman's boyfriend turned the gun on himself once deputies arrived. He died at the scene.
Investigators said the two brothers who were killed were in their 30s and 50s.
While looking at the scene, deputies said this was not the first time law enforcement was called to this home.
Officials said just a few days earlier, there had been a family violence call between the woman and the boyfriend, but details on the incident were limited.
No names have been released of the victims, and officials said the surviving brother, the woman, and her two kids are said to be OK and are cooperating with law enforcement.
If you need help or know someone in need of help, please call the National Domestic Violence Hotline for confidential support 24/7/365. The number is 1-800-799-SAFE (7233). You can also text the word "START" to 88788.