WINTHROP (CBS) – Aria Green said his brother, retired Massachusetts State Police Trooper Dave Green, died on Saturday doing what he did throughout his life – trying to help others.

Dave Green was one of two people shot and killed by 28-year-old Nathan Allen in Winthrop, according to investigators. Allen allegedly crashed a stolen tractor-trailer into a building, then fatally shot Dave Green and Air Force veteran Ramona Cooper.

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The scene of a stolen truck crash in Winthrop. (Photo Credit: WBZ-TV)

District Attorney Rachael Rollins said Dave Green and Cooper were targeted because they were Black. Investigators say they discovered Allen had racist and anti-Semitic writings.

Allen was shot and killed by Winthrop Police during an exchange of gunfire.

Aria Green flew to Winthrop from Florida following his brother’s death. The family has been well-known in the town for decades.

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“He was such a wonderful person. It was so unexpected. It’s not like someone was ill and you were expecting it,” Aria Green said about his brother’s death. “He was such a good person. I’m not just saying that because he’s my brother. He was just a good, kind-hearted person.”

Retired Massachusetts State Police Trooper Dave Green was shot and killed in Winthrop. (Family Photo)

Dave Green became a Metropolitan District Commission Police Officer in 1980, joining the Massachusetts State Police 12 years later when the MDC Police and State Police merged. He retired in 2016.

Prior to becoming a police officer, Dave Green served in the military.

Investigators believe he heard the sound of the truck crash on Saturday, and came out to see if he could help. Instead, he was shot and killed.

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“Some people are nice. He was kind. He would help anybody at any time without even being asked. And that’s what happened here. He heard there was an accident, he went to investigate and see if he could help, which is something he would readily do,” said Aria Green. “He spent his life serving the community … He’s always been in service. I guess he kind of died the way he lived.” Staff