(CBS) - Aaron Alexis, the suspected gunman in Monday's shooting rampage at the Washington Navy Yard, was arrested in Seattle in 2004 for allegedly shooting out the tires of another man's car in what detectives described as an anger-fueled "blackout," Seattle Police said in a blog post Monday.
Alexis' father told Seattle detectives that Alexis had been a responder in New York on Sept. 11, 2001, and that his son had anger management problems associated with post-traumatic stress disorder, says the Seattle Police Department.
Police say Alexis also told them he was present during "the tragic events of September 11, 2001" and described "how those events had disturbed him."
Officials said 12 innocent people were killed at the Navy Yard Monday, as well as Alexis, and at least a dozen more were injured. A law enforcement official told CBS News the shooter apparently had a handgun, an AR-15 assault rifle, and a shotgun with him and was wearing dark blue clothing.
A motive wasn't immediately clear, and police were on the lookout for a possible second suspect they said was seen armed and wearing military gear near the site of the shooting.
Seattle police posted details about the May, 2004 incident and the original police report on their website Monday in response to numerous inquiries.
According to the post, at that time Alexis had been staying near a construction site in Seattle's Beacon Hill neighborhood. Two construction workers there reported seeing Alexis walk out of his home, pull a gun from his waistband and fire three shots into the two rear tires into a 1986 Honda owned by one of the workers before slowly walking back to the home.
Workers and a manager at the construction site reportedly told Seattle police Alexis "stared" at the workers each day for about a month before the shooting, saying they believed he was angry about the parking situation near the worksite.
Police reportedly later arrested Alexis after finding a gun and ammunition in his room in his grandmother's home, where he had been staying. After his arrest, Seattle police reported he told officers he felt "mocked" by the workers and felt they had "disrespected him." He claimed his anger caused a "blackout" and that he couldn't remember the incident until about an hour after he fired the shots at the car.
A continuing records check uncovered that Alexis had a concealed pistol license and a Glock .45 caliber gun registered to him, according to a police report made public on the Seattle Police Department's website. He was booked for malicious mischief, according to the report.
Alexis was also was arrested in September 2010 for allegedly firing a gun inside his Texas apartment, reports the Ft. Worth Star-Telegram.
According to the Star-Telegram, friends say Alexis was in the Navy from 2007-2011, but left because he didn't like waking up early. The Associated Press is reporting that Alexis was a former Navy reservist stationed in Ft. Worth.
The newspaper interviewed a man named Nutpisit Suthamtewakul, who described Alexis as his "best friend," and said he knew his former roommate had a gun but "didn't seem aggressive to me."
The Star-Telegram reports that the 2010 incident did not result in charges against Alexis, but that his landlord at the apartment where he was arrested began eviction proceedings against him and Alexis moved out in November of that year.
At a press conference Monday afternoon, the FBI urged anyone with information about Alexis to come forward, saying they were looking for any information regarding Alexis' recent movements, contacts and associates.
"No detail is too small," said Valerie Parlave, an assistant director in charge of the Washington FBI field office. "We will continue to run down every lead."