The Navy Yard gunman who killed 13 yesterday, had previously claimed to be suffering from post-traumatic stress disorder (PTSD) after helping in rescue efforts in New York, following the 9/11 terror attacks.
Gunman Aaron Alexis was shot dead by responding officers after he opened fire inside a Navy facility on Monday morning, killing 12 people.
It emerged that he used three guns during the massacre, one of them an AR-15 semi-automatic rifle -- the same weapon used in the Sandy Hook and Aurora mass shootings.
He was killed in one of the several running gun battles with the police, after he entered the Naval Sea Systems Command headquarters and started picking off victims in a cafeteria from a fourth-floor atrium, witnesses said.
The motive for the mass shooting was a mystery, investigators said.
But a profile of the lone gunman, a 34-year-old Aaron Alexis, was coming into focus. He was described as a Buddhist who had also had flares of rage, complained about being a victim of discrimination, and had several run-ins with the law.
Alexis, who was a defence contractor, had been hearing voices in his head and was suffering from paranoia and a sleep disorder. He had been treated since August by the Veterans Administration for his mental problems, the officials said.
Alexis was arrested over gun-related incidents in 2004 and 2010 in Fort Worth, Texas, and Seattle, and was described in police reports as ‘seething with anger’.
The police report also said Alexis -- who was discharged from the navy in 2011 -- had been traumatised by being present at the 9/11 attacks.
Seattle police said in May 2004 that Alexis -- a convert to Buddhism who grew up in New York City -- shot out the tyres of a car, claiming he had been traumatised by the 9/11 attacks.
In April 2010, Alexis was arrested for shooting a bullet through his apartment ceiling in Fort Worth. He claimed that the weapon went off accidentally when he was cleaning it.
Alexis had been a full-time Navy reservist from 2007 to early 2011, but his military service was marked by disciplinary problems. He was discharged for misconduct, but he did receive two medals during his service -- both were issued to large numbers of service members who served since the 9/11 attacks.
Outside the Alexis family home in Brooklyn, Alexis’ brother-in-law, Anthony Little, said his relatives were distraught.
“Their hearts are going out more to the victims who got hurt, because, you know, it’s more lives lost and we don’t need that right now,” Little said.
Latest in a long line of deadly US killings
There have been six mass shootings over the past nine months -- and at least 20 during Obama’s presidency. Many said they were no longer surprised about the shootings, raising the debate of gun control in America.
April 2, 2012 - A gunman kills seven people and wounds three in a shooting at a Christian college in Oakland, California.
July 20, 2012 - A masked gunman kills 12 people and wounds 58 when he opens fire on moviegoers at a showing of the Batman film ‘The Dark Knight Rises’ in Aurora, a suburb of Denver. A 24-year-old former university student is charged in connection with the rampage.
August 5, 2012 - A gunman kills six people during Sunday services at a Sikh temple in Oak Creek, Wisconsin, before he is shot dead by police.
December 11, 2012 - A gunman opens fire inside an Oregon shopping mall, killing two people and wounding one. He then kills himself.
December 14, 2012 - A heavily armed gunman kills 20 children and six adults at an elementary school in Newtown, Connecticut. Before the rampage, the 20-year-old shooter first shot and killed his mother in their home. When authorities approached the school, the shooter turned the gun on himself.
September 16, 2013 - A 34-year-old man opens fire at the US Navy Yard in Washington in an incident in which 13 people, including the gunman, are killed.
Indian-American among 13 killed
Vishnu Pandit, a 61-year-old Indian-American man, is among the 12 people who were killed by a gunman in a deadly mass shooting at the naval base.
How the shootings took place
>> Monday’s violence began at 8:20 am, when several shots broke the workday calm of the south-east Washington facility.
>> DC Metropolitan Police officials said that Alexis drove into the installation and parked, before walking a short distance to Building 197, where the killings occurred.
>> Alexis had an active ID and entered the base legally, a federal law enforcement official said.
>> Once inside, according to an official, Alexis made his way to an overlook above the atrium and opened fire.
>> Two witnesses said that they heard a fire alarm go off in the building where they worked, and then saw a man with a rifle down the hallway as they left the building.
>> “He aimed the gun and fired our way,” said Todd Brundidge.
>> People frantically ran downstairs to get out of the building, Brundidge said.
>> “They were pushing. They were shoving. People were falling down,” Brundidge said. “As we came outside, people were climbing the wall trying to get over the wall to get out. It was just crazy.”
>> Following the incident, US President Obama made a statement, calling those who had been shot at the naval base ‘patriots’, and expressed his grief at another mass shooting.
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