Family members and friends are mourning the two longtime public servants who were killed by a gunman in Winthrop on Saturday.
Police say Nathan Allen, 28, of Winthrop, rammed a building in a stolen truck, then fatally shot David Green, a retired state police trooper, and Ramona Cooper, an Air Force veteran, before police killed him.
Green, 58, who grew up in Winthrop, spent 36 years in law enforcement.
"My brother had a unique ability — I think it was unique — he was able to talk to people," said Green's brother, Ray Green.
Ray says David never married. David took care of their older parents before they died and was known in the community as someone who was always willing to help a friend or neighbor, whether it was with a flat tire or taking a sick dog to the vet.
"That's the type of person he was, all the time, all throughout his life," Ray Green said.
But on Saturday, David Green became a victim of a ruthless crime in an alley near Shirley Street in Winthrop.
It was right after Allen, a physical therapist who recently received his doctorate from the MGH Institute of Health Professions, crashed a truck into a nearby house. Allen climbed out with a gun and allegedly began shooting people.
His first victim, prosecutors said, was Ramona Cooper, 60, a retired Air Force sergeant who was walking across the street. Authorities said she was shot three times in the back.
Both Green and Rollins were Black and their murders are being investigated as possible hate crimes.
Suffolk County District Attorney Rachael Rollins told WBUR Monday that investigators found evidence of racist writing in the shooter's house — including anti-Semitic language and swastikas.
Rollins says the shooter walked right past a number of people in Winthrop but then shot Cooper and Green, who were Black.
Northeastern University criminologist Jack Levin said the killings appear to fit a pattern of recent race-fueled attacks.
“There's a much larger group of white supremacists who were inspired by organized hate groups on the right," Levin said, "who give to these individuals what they never got before. And that is a feeling of power.”
Levin says the Winthrop killings could be a copycat attack, pointing to other lone wolf white supremacists using vehicles for deadly violence.
Nick Tsiotis heard about the shooting and was immediately worried about Green, who he'd just seen that morning.
So Tsiotis sent him a text, warning Green "there's a shooter on the loose" and asking him to please let him know he was OK. He never heard back. But he suspects Green got killed trying to help others.
"I had this feeling that if anyone was going to intervene and run right into the chaos it would be Dave to try to help save other people's lives," Tsiotis said.
Green was shot four times in the head and three times in the torso before police shot and killed the gunman. Tsiotis calls Green a hero.
"David Green was the best of what humanity offered. He led a life of personal excellence, and he really cared for others."
According to a statement from the State Police, “Trooper David Green more than upheld the ideals of integrity, professionalism, and service to others that are the hallmarks of a great trooper. We are heartbroken by his loss.”
Cooper, the gunman's first victim, is also being remembered — for her service to the country as an Air Force veteran, and as a mother and grandmother.
"She's a good person," her son, Gary Cooper Jr., told WCVB.
Cooper told the station that his mother was caring and selfless. Cooper said she was still working with veterans right up until her untimely death.
"I got sick to my stomach when I found out it was racially motivated," he said.
Impromptu memorials to honor Cooper and Green have popped up in Winthrop. The town is planning a candlelight vigil Thursday evening.
This segment aired on June 28, 2021.