He was a student.
From SF Chronicle:
The gunman shot by UC Berkeley police at the Haas School of Business was a student and has died at a hospital, a university spokesman said today.
The name of the 33-year-old student was not immediately released.
UC Berkeley spokesman Dan Mogulof said the student had recently transferred to the campus as an undergraduate, and this was his first semester there.
The man was brandishing a handgun in the business schools' computer lab when he was confronted by several university police officers about 2:20 p.m. Tuesday, police said. One officer fired at the suspect, who died later in the day at Highland Hospital in Oakland, Mogulof said.
Not enough facts have emerged in this case to draw any kind of conclusions, but I'd love to hear from some witnesses who aren't police.
10:39 AM PT:
Update from The Bay Citizen:
Susie told Lyle Nevels, the business school's chief information officer, what she had seen, and the pair went into the third-floor computer lab. They saw the man, whom Nevels described as white, in his mid-20s, wearing jeans and with short, brownish-grayish hair, sitting at a computer. A gun was not visible at that time.
They called the University of California Police Department, which sent three officers to respond. When the police entered the computer lab and approached the suspect, he pulled the gun out of his backpack in a threatening manner, Celaya said.
Alex Arroyo and Loren Fuell, Berkeley students who work at the computer lab, were sitting at a desk outside the lab at the time of the shooting. They said they heard the officers say repeatedly, "Drop the gun," before four or five shots were fired.