Neighbors tried to stop an assault in a Boston neighborhood. But one was stabbed to death, cops say.

A fight between neighbors in a Boston neighborhood left one man dead and a suspect under arrest, police said.

Around 8 p.m. on Jan. 26, officers responded to a 911 call reporting a stabbing in Roxbury, the Boston Police Department said.

At the scene, officials said they found one victim suffering from a stab wound to the chest and a second victim suffering from multiple stab wounds.

Both stabbing victims were taken to Boston Medical Center. One victim, identified as 33-year-old Ronald Reed, was pronounced dead from his wounds and the second man suffered non-life-threatening injuries.

According to authorities, the suspect, 42-year-old Raymond Vega-Castro, assaulted the victims’ neighbor. That caused the surviving victim to get involved, as Reed also intervened, NBC Boston reported. Vega-Castro then allegedly stabbed both victims.

Vega-Castro was arrested and charged with murder, assault to murder and a warrant for violation of probation, police said.

He was ordered to be held without bail, officials said.

“This was a senseless act of violence that stole one man’s life, left another man injured and forever changed the lives of those impacted and their loved ones," said Suffolk County District Attorney Kevin Hayde. "It has also traumatized the community and those who witnessed this tragic act of violence. I’m grateful to the community members who came forward to assist in this investigation, and to the members of law enforcement who acted with diligence to identify, locate and apprehend this individual," NBC Boston reported.