Mass shooting at D.C. Navy Yard

[Stephan Bobb]

Mass shooting at D.C. Navy Yard

Washington (CNN) -- While no specific reason has been given as to what spurred him to shoot dead 12 people at Washington's Navy Yard, Aaron Alexis' overall mindset came into sharper focus Tuesday -- including a history of psychological issues.

That past includes a Newport, Rhode Island, incident on August 7, more than five weeks before Alexis was gunned down after single-handedly pulling off America's latest mass shooting.

Describing himself as a Navy contractor, Alexis told police he believed an individual he'd gotten into a verbal spat with had sent three "people to follow him and keep him awake by talking to him and sending vibrations into his body," according to a police report. Alexis said he hadn't seen any of these people, but insisted they'd followed him between three hotels in the area -- the last being a Marriott, where police investigating a harassment complaint encountered him.

If you have information regarding Aaron Alexis or the Navy Yard shooting, call 1-800-CALL-FBI or visit the FBI's website.

Read the police report

There, Alexis told authorities the unseen individuals continued speaking to him through walls and the floor, and that they used "some sort of microwave machine" to send vibrations into his body to keep him awake.

Police: Navy Yard shooter heard voices

He added, according to the police report, that "he does not have a history of mental illness in his family and that he never had any sort of mental episode." Nonetheless, a police sergeant alerted authorities at Naval Station Newport about Alexis "hearing voices." Reached Tuesday, officials at the base referred CNN to the FBI, which declined comment.

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It's not known if this incident was in any way related to Monday's shooting spree. Still, it and other details offer insights into the shooter -- and raised questions as to whether he could have been stopped.

Gunman passed security clearances

The Navy moved to discharge Alexis in 2010 because of what two Navy officials described as a "pattern of misconduct" described as a history of disciplinary issues.

There were also run-ins with police, beyond the Newport incident. In Seattle, for instance, Alexis was arrested in 2004 for shooting out the tires of another man's vehicle in what he later told detectives was an anger-fueled "blackout."

DeKalb County, Georgia, authorities said Tuesday they arrested Alexis in 2008 on a disorderly conduct charge.

And recently, Alexis had contacted two Veterans Affairs hospitals -- possibly seeking treatment for psychological issues -- two law enforcement sources told CNN.

Whatever his past, Alexis was a military contractor and was in the Navy's Ready Reserve -- a designation for former military members who don't actively serve in a Reserve unit but who can be called up if the military needs them.

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Moreover, he had legitimate credentials to enter the base, Valerie Parlave, assistant director in charge of the FBI's Washington field office, said Tuesday. He also had a secret security clearance valid through 2017, even after leaving the service full-time in 2011, Navy spokesman John Kirby told CNN.

Still, among the big questions Tuesday were whether he should have had either -- and, even if he did, how he was able to walk onto a naval base armed, then begin firing.

Investigators scour crime scene, hotel and beyond

The historic Navy Yard will remain closed to all but "essential" Navy employees Wednesday, as it was Tuesday. Even then, it's likley to remain abuzz with investigators methodically modeling bullet trajectories and mapping the scene, according to Parlave.

Federal law enforcement sources say authorities recovered three guns from the scene: a shotgun and two handguns.

Two days before the shooting, Alexis spent "a couple hours" shooting at Sharpshooters Small Arms Range in northern Virginia before paying $419 for the Remington 870 shotgun -- after being approved by the federal background check -- and a small amount of ammunition, the store's attorney, J. Michael Slocum, said.

The two handguns, sources say, may have been taken from guards at the naval base. But how Alexis brought the shotgun in, though, remains an open question, with Washington Mayor Vincent Gray speculating he may have concealed it.

Parlave said that Alexis is believed to be solely responsible for Monday's bloodshed -- in which he parked, walked into Building 197 at the facility, made his way to an overlook above the atrium and opened fire. Still, that doesn't mean authorities aren't looking into others who might have helped him, wittingly or unwittingly, or known something about the plot.

Who is Navy Yard gunman Aaron Alexis?

Who was Aaron Alexis?

Shawn Henry, a former executive assistant director of the FBI, told CNN that he expects the investigation will stretch across the United States -- including "looking at people that have known Alexis for many years, people that he might have gone to school with, people he served in the military with."

Tragedy at the Washington Navy Yard

"They'll be looking at bank records, they'll be looking at cell phone records, trying to piece together all of those pieces," added Henry, now president of the security firm Crowdstrike Services, on Tuesday, the same day FBI agents were seen hauling boxes from the hotel where Alexis had been staying.

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Terrorism hasn't been ruled out but seems unlikely, Gray told reporters.

Investigators will make efforts to determine if Alexis had contacts with anyone at the facility, or if he had conducted reconnaissance in advance of the mass shooting, said Henry. They're also appealing for the public's help in a probe that U.S. Attorney Ronald Machen estimates could take "weeks and months."

"No piece of information is too small," Parlave said.

'Who was this guy?'

That's especially true for information about Alexis himself.

A New York City native -- where both his parents, now divorced, still live -- Alexis worked between 2001 and 2003 at the Borough of Manhattan Community College. His supervisor there, Barry Williams, told CNN he never would have expected such a violent outburst, though Alexis would get easily frustrated over minor things and hold grudges.

Years later, Alexis worked in the Navy as a petty officer working on electrical systems.

But his four years in service weren't all smooth, as he developed a history of disciplinary issues, including eight instances of misconduct while on duty, a U.S. defense official told CNN. Those incidents included cases of insubordination, disorderly conduct, unauthorized absences and at least one instance of intoxication, the official said.

"He wasn't a stellar sailor, we know that," said Rear Adm. Kirby, adding that the misconduct cases were all "relatively minor." "... None of those (offenses) give you an indication he was capable of this sort of brutal, vicious violence."

Those military offenses were not enough to warrant a general discharge, and without a civilian conviction, the military resorted to an honorable discharge in January 2011, the official said. And Alexis was still part of the Navy's Ready Reserve, Navy Secretary Ray Mabus told CNN.

Vetting military contractors: How did gunman get in?

A friend and former housemate, Kristi Suthamtewakul, told CNN's "New Day" that she had noticed personality changes in Alexis over the last few months, but nothing indicating the potential for such violence.

"Aaron was a very polite, very friendly man," she said.

Among other problems, he had been frustrated about pay and benefits issues after a one-month contracting stint in Japan last year, Suthamtewakul said.

"He got back and he felt very slighted about his benefits at the time," she said. "Financial issues. He wasn't getting paid on time, he wasn't getting paid what he was supposed to be getting paid."

"That's when I first started hearing statements about how he wanted to move out of America," Suthamtewakul said. "He was very frustrated with the government and how, as a veteran, he didn't feel like he was getting treated right or fairly."

Another friend, Texas resident Michael Ritrovato, also said Alexis had recently been frustrated with his employer over pay.

But Ritrovato said his friend never showed signs of aggressiveness or violence, though he played a lot of shooting video games online.

"It's incredible that this is all happening, because he was a very good-natured guy," Ritrovato said. "It seemed like he wanted to get more out of life."

Melinda Downs described Alexis as "very intellectual" and of "sound" mind -- saying if he did hear voices, "he hid it very well." The two spoke as recently as a week ago, at which time Downs said she had no hints of what was to come,

"It is like Dr. Jekyll and Mr. Hyde," she said. "Who was this guy?"

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Recovery for some, mourning and reflection for others

Monday's shooting was the worst since December's mass killing at Sandy Hook Elementary School in Newtown, Connecticut. Gunman Adam Lanza killed 23 people, 20 of them children, in that incident.

In addition to the Senate's moment of silence, Defense Secretary Chuck Hagel -- who ordered a review of security measures at U.S. military bases after the attack, according to a senior Pentagon official -- laid a wreath at Navy Memorial plaza. Flags over government buildings also flew at half-staff.

Eight people wounded in the shooting continued their recoveries at Washington-area hospitals. That includes three at MedStar Washington Hospital Center, all of which showed improvement Tuesday, according to doctors. Also recovering from surgery for gunshot wounds to his leg and in good spirits is Washington police Officer Scott Williams, who the city's mayor said ended the 30 minutes of off-and-on shooting by killing Alexis.

That includes one woman who was hiding underneath her desk when the gunman came by. The bullet grazed the finger of her upheld hand and went into the scalp behind her right ear, said Dr. Jane Orlowski, chief medical officer at the hospital.

"Thankfully, it sort of hit the bone and bounced off," Orlowski told CNN's "New Day." "She is an extremely lucky young lady."

For others in Washington, life returned to normal Tuesday. Streets near the base were mostly open, and a Washington Nationals baseball game delayed Monday after the shootings was played. Still, the shooting remained a topic of conversation for many.

In remarks Tuesday, Senate Majority Leader Harry Reid said the nation's thoughts were with those who had lost loved ones.

"There are no words that can possibly ease the pain of the rampage and certainly the deaths involving a dozen human beings who were killed yesterday at the naval yard," said Reid. "I hope it is some small comfort that this city, this institution of the United States Senate and the whole nation mourn right alongside them."

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