Washington Yard shooter: What is Microwave hearing?

On Tuesday, the Washington Navy Yard shooter's stepfather Frank Calderon said that Aaron Alexis was walking out of the World Trade Center subway stop on 9/11 when the first tower collapsed, and that he stayed to help pull bodies from the rubble.

"Aaron said he was on the escalator coming up from the subway station when he saw the building come down. It was right in front of him, and he said he saw it collapse,"

"That day was traumatic for everyone involved. He did not talk much about it, but he said he helped out. He was a strong young man, so he would have done what he could."

But was Aaron Alexis really that strong?

Navy Yard shooter: FBI asks public for help in finding information about deceased Navy Yard shooter, Aaron Alexis

Navy Yard shooting: The FBI is asking the public for help in finding out more information about the deceased Navy Yard shooter who is responsible for Monday's deadly rampage at the Washington Navy Yard.

The Navy Yard shooter, 34-year-old Aaron Alexis is a civilian contractor from Fort Worth, Texas, and was identified by the FBI through his fingerprints.

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