Who caused the Betty Court fire? Are witnesses afraid to speak up?

When the Betty Court fire initially happened, a tipster contacted me with this information. I just recovered the message.

"The local loiterer lives across the street. So a local loiterer told me that his friend Richard,  a recently homeless man was burned.  He also said a first responder was injured. He also said there was a teenage party across the street that was broken up by a parent.  Then apparently a car windshield was broken out. He assumed that Richard was in the gym and thinks maybe the kids could've been a party to the fire."

The tipster  tried to call local enforcement and got an answering machine so left no message.

HCSO Press Release:

On Tuesday, October 25, 2016, Humboldt County Deputies were dispatched to the 1500 block of Betty Ct, where the Big Lagoon Rancheria’s Gym had once stood. Deputies met with Arcata Fire District Investigators determined the cause of the fire to be “human involved.”

The Sheriff’s Office is requesting assistance from the public in identifying the person(s) responsible for the fire.

The estimated damage to the gym and surrounding buildings is over $3,300,000.