SAN FRANCISCO (KGO) -- Last November, 57-year-old Dan Jansen could be seen on surveillance cameras setting-up barricades around the old Bank of America Building at 555 California Street.
Signs on the building clearly state that skateboarding is not allowed but, surveillance video shows at least one skateboarder attempting to move the barricades.
In the video, viewers can see the atmosphere escalate. Jansen is surrounded and then hits the ground.
RELATED: Security guard working outside former Bank of America Center in San Francisco critically hurt in attack
Investigators said Jansen was swarmed by the skaters and assaulted by 24-year-old Jesse Vieira.
ABC7 News was the only crew on the scene as first responders rushed Jansen to the hospital. Brain swelling forced doctors to remove part of his skull.
"Nothing will change what they did, but I don't want it to happen to somebody else," Susanne Andrews, Jansen's sister said.
RELATED: ONLY ON ABC7NEWS.COM: San Francisco security guard attacked by skateboarder is out of coma, but not well, family says
Vieira is a sponsored star skater and has been featured in publications like Thrasher Magazine. He also has a large following in the skating community.
Throughout Vieira's trial, the defense claimed Jansen assaulted Vieira first. They also said Jansen went after the smallest guy in the group.
The state described the encounter as a brutal attack with life altering effects.
RELATED: Suspect accused of attacking San Francisco security guard is well-known skateboarder
Jansen's family tells ABC7 News he's in an assisted-living facility, can't walk, and is just now beginning to recognize family.
The jury left San Francisco's Hall of Justice shortly after 4 p.m. on Thursday. Deliberations will resume on Monday.
San Francisco jury begins deliberations in alleged skateboarder attack
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