EAST LANSING, Mich. -- Years before Anthony Dwayne McRae killed three Michigan State University students and critically wounded five others, he was charged with carrying a concealed weapon -- a felony count that would have prevented him from being able to buy a gun if he were convicted.
That felony case never went to trial. Instead, a 2019 deal allowed McRae to plead guilty to a misdemeanor -- possession of a loaded firearm in or upon a vehicle, the Ingham County prosecutor's office said Tuesday. McRae spent a year and a half on probation.
Now, questions abound over whether the slaughter at Michigan State on Monday evening could have been prevented.
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McRae purchased two guns in 2021 in Michigan, a law enforcement source said. One was a Taurus pistol, and the other was a Hi-Point 9 mm pistol, according to the source.
It's not clear whether either of those two weapons was used in the deadly rampage that spanned two parts of the campus in East Lansing.
It's also unclear why McRae -- a 43-year-old with no known ties to MSU -- targeted the university. He died from a self-inflicted gunshot wound hours after the first shots rang out on campus Monday, police said.
But the assailant had a note in his pocket that threatened other shootings hundreds of miles away in New Jersey, authorities said.
McRae, who grew up in New Jersey, said in the note that there were "20 of him" who will carry out shootings, according to a source familiar with the investigation.
The note "indicated a threat to two Ewing Public Schools," police in New Jersey said Tuesday. But after McRae was found dead, Ewing police said there was no longer a threat in New Jersey.
It's not clear why McRae might have planned to target schools in New Jersey. Ewing police said the "investigation revealed that McRae had a history of mental health issues," but did not elaborate.
The suspect's father, Michael McRae, told CNN his son became bitter, isolated and "evil angry" after his mother died from a stroke two years ago and "didn't care about anything no more."
Michigan Democratic Gov. Gretchen Whitmer, in a video statement posted to Twitter, promised legislative changes.
"The time for only thoughts and prayers is over," Whitmer wrote in the accompanying tweet. "We are in a unique position to take action and save lives. And that's exactly what we are going to do in the weeks ahead."
In the video, she called deadly mass shootings a uniquely American problem.
"Too many places in our nation that are supposed to be about learning and community or joy have been shattered by bullets and stained by bloodshed," Whitmer said. "We shouldn't have to live like this."
Whitmer also spoke Wednesday evening at a vigil on campus, where hundreds of students, faculty, staff and community members gathered with flowers to honor Arielle Anderson, Alexandria Verner, and Brian Fraser.
Jo Kovach, Michigan State student body president, urged her fellow students to support each other and to remember there is no rulebook on how to mourn.
"We just have to live each day from here on out, reaching out for help when we need it and getting through the harder days together," Kovach said. "I cannot tell you how we go forward, but I will tell you that Spartans will heal together."
Investigators hunt for answers
After his 2019 plea deal, McRae's probation was "extended a couple of times," Michigan Attorney General Dana Nessel told CNN.
Nessel -- who has two sons at the university shaken by this week's tragedy -- said she wants to know why.
"This is an individual who just recently was off probation for a gun offense and in the exact same area," Nessel said. "We know that he had his probation extended a couple of times and not sure why, and I'd like to know that."
In another CNN appearance, Nessel told told Wolf Blitzer on CNN's "The Situation Room" she doesn't think the gunman shouldn't have been able to buy a weapon.
"Somebody who is having mental health issues, somebody who just had been illegally possessing a gun, and look how easy it was for him to obtain a weapon even in the wake of all that. Something's gotta change," she said from the site of the vigil.
MSU police said Thursday McRae was found with two 9 millimeter weapons and additional ammunition. The firearms were purchased legally, but were not registered properly.
Nessel said it wasn't clear yet whether the gun used in shooting was purchased legally.
"We don't even have universal background checks here in Michigan," Nessel added. "We have very little in the way of legislation that would prevent a person from possessing a gun, owning a gun, coming into contact with a weapon."
She said she thought now that the Michigan Legislature is controlled by Democrats, that will change.
Among the other questions still unanswered:
Whether McRae knew anyone on campus.
What type of firearm was used in the mass shooting and whether it was one of the guns McRae purchased in 2021, following his plea deal.
Why McRae was able to purchase two guns in Michigan in 2021, after he had pleaded guilty to a misdemeanor firearms charge. At the federal level, a misdemeanor conviction does not preclude someone from buying a gun. But in Michigan, "the charge under Michigan law is either a low-class felony or high-class misdemeanor," the state attorney general's office said. So "for the purposes of being able to legally possess a weapon, it's considered a felony."
3 beloved students are dead as 5 others fight for their lives
As parents frantically tried to contact their children after the mass shooting, three families received the worst news imaginable.
Juniors Arielle Anderson, 19, and Alexandria Verner, 20, and sophomore Brian Fraser, 20, were killed in the attack, university police said.
Anderson was studying to become a doctor, her aunt Chandra Davis posted on Instagram.
"How is it that she was in class doing what she was supposed to be doing and yet and still her life was taken by a coward who clearly didn't understand the devastation he was about to cause my entire family," Davis wrote. "No parent should have to bury their children."
Anderson was planning to graduate early to become a surgeon as quickly as possible, her family told CNN affiliate WDIV.
"As much as we loved her, she loved us and others even more," Anderson's family said in a statement to WDIV. "She was passionate about helping her friends and family, assisting children and serving people."
Anderson graduated from the Grosse Pointe school district -- just like Fraser, another student who was killed, Superintendent Jon Dean said.
The tragedy "touched our community not once, but twice," Dean said.
Fraser was president of the Michigan Beta Chapter of Phi Delta Theta, the fraternity said in a statement.
He was a leader and a great friend to his brothers, the Greek community and the people he interacted with on campus, the fraternity said.
He will be buried Saturday, according to an official at St. Paul on the Lake Catholic Church.
And Verner, a graduate of Clawson Public Schools, was "everything you'd want a student to be," school district Superintendent Billy Shellenbarger said.
"Her kindness was on display every single second you were around her," said Shellenbarger, who is also friends with Verner's family.
Verner's funeral is scheduled for Saturday morning, the superintendent said.
The mass shooting left five other students in critical condition, but officials said during a news conference Thursday morning there were some signs of improvement. One had been stabilized.
While authorities have not identified them, student Guadalupe Huapilla-Pérez is one of the wounded, according to a verified GoFundMe account and the National HEP/CAMP Association, which Huapilla-Pérez participated in at school.
"Sadly, we now know that a CAMP student attending Michigan State University was one of the victims of this horrific mass shooting," the organization said on Facebook. "Guadalupe (Lupe) Huapilla-Pérez is currently recovering from serious injuries related to the shooting. The time away from work for her family, the long recovery road ahead, and the subsequent medical expenses to care for Guadalupe, will place both an emotional and financial a burden on her family."
The organization, which serves students from migrant or seasonal farmworker families and is funded through grants by the US Department of Education and Office of Migrant Education, posted a link to a verified GoFundMe campaign that was set up by Huapilla-Pérez's older sister, Selena.
"Lupe is a current Hospitality Business junior at MSU and student in the Michigan State University College Assistance Migrant Program (CAMP)," her sister said on the GoFundMe page.
"She is a leader in the community and beyond. Lupe is incredibly hard-working, focused, and ambitious, choosing a career path that's never been explored in our family."
Berkey Hall, where the gunman first opened fire, will remain closed for the rest of the semester, officials said Thursday. The student union is still being evaluated by investigators.
Classes at the university remain suspended until Monday, but campus offices are reopening Thursday.
There are ongoing discussions about offering students an option to complete the semester remotely.
What we know about the gunman
A search warrant was executed on a home connected to the suspect, but authorities have not yet confirmed what they found there.
McRae had lived with his father in a small house in Lansing. The suspect's father said about 30 police officers came to his house and went through his son's bedroom.
Michael McRae said his son grew reclusive when his mother, Linda, died.
"Ever since my wife died, my son began to change," Michael McRae said. "He was getting more and more bitter. Angry and bitter. So angry. Evil angry ... He began to really let himself go. His teeth were falling out. He stopped cutting his hair. He looked like a wolf man."
The father said he believed his son had obtained a gun but kept it in his room and denied to his father that he had it.
'We now have a complete generation who has grown up with this'
The carnage at Michigan State led to a painfully familiar scene: Terrified students barricading classrooms with furniture, jumping out of windows and running for their lives.
"We now have a complete generation that has grown up with this, many times over, from elementary school all the way up to now," East Lansing Mayor Ron Bacon said. "They live with this the entire time."
One parent said his daughter, Emma, has survived two campus school shootings in less than 15 months.
When gunfire broke out at Oxford High School in November 2021, Emma hid inside the band hall of Oxford High School where others had barricaded the door. The students eventually fled out of an exterior door to a store in the area, her father Matt Riddle said.
This week, the 18-year-old found herself hiding from a gunman once again.
Emma told her dad that she and her roommate shut the lights off, closed the window, barricaded the door, and hid under their desks after they received the university alert about shots fired.
"Tonight, I am sitting under my desk at Michigan State University, once again texting everyone 'I love you'" Emma tweeted Monday. "When will this end?"
ABC News contributed to this report.
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