The man who killed two people in a shooting rampage in Winthrop, Massachusetts, last month wrote less than two days earlier that "Racism is healthy and natural" in a bigoted, hateful screed revealed by officials Wednesday.
The information comes from journals kept by the gunman and found at his apartment, Suffolk County District Attorney Rachael Rollins said.
"This man had fooled so many, outwardly appearing stable and upstanding while internally filled with extremist ideologies and hatred," she said in a statement.
On Saturday, June 26, the man -- identified as Nathan Allen -- crashed a plumbing truck he stole into a building, then got out and gunned down two Black people before being killed by police. Authorities have been investigating the shooting as a possible hate crime.
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The 28-year-old gunman's writings are racist, spewing hatred about Black people and asserting that the white race is superior, as well as sexist, saying that women don't understand men. Much of it is unrepeatable, using slurs and advocating violence -- he called white people "apex predators" and drew swastikas, a symbol coopted by the Nazis.
"Racism is healthy and natural. And holding it in is bad for you," he wrote in the diary on the night of June 24, prosecutors said, after listing racist grievances against Black people.
The man's family has been cooperative with investigators and devastated by the deaths of his two victims, retired Massachusetts state trooper David Green and Air Force veteran Ramona Cooper, Rollins said.
Rollins' office is still reviewing the "volumes of extremist literature" that the man read frequently over the past several months, according to a news release.
Winthrop police Chief Terence Delehanty spoke to reporters after the release of excerpts of the journals. He emphasized that the gunman wasn't born or raised in Winthrop and that the community is far better represented by the way it came together in mourning after the shooting.
"The ideology, white supremacy, that he subscribed to is despicable to all of us," Delehanty said.
He said the FBI is part of the investigation into what happened. The probe has been focused in part on where the man became radicalized.
The shooter received a doctorate in physical therapy in January, the MGH Institute of Health Professions has confirmed. He'd started attending the school, a graduate school for health professions, in 2017.
Authorities have previously said that the shooter passed by people who were not Black during the brief rampage -- two people who said they came face-to-face with the gunman and were not shot described him looking right at them.
Two handguns were found on the man after he was killed by police, who were arriving to help after the truck crash and whose actions were praised again Wednesday by Rollins and Delehanty.
Rollins also noted that there has been a "disturbing rise in hate crimes across the country" in the last few years, and pointed to the repeated stabbing of a rabbi in Boston last week, which is also under investigation as a possible hate crime.
"Who you are, love, pray to, or identify as, is fundamental. It must be fiercely protected. ... We have seen this in the beautiful outpouring of support shown by the members of the Winthrop and the Brighton communities that have said loud and clear, 'Hate has no place in Suffolk County,'" she said in her statement.