Retired mixed marshal arts star Tim Kennedy said he was “flabbergasted” when he learned that Matthew Livelsberger is believed to be behind the Jan. 1 blast that injured 7.

Matthew Livelsberger -- the driver of the Tesla Cybertruck that exploded outside the Trump International Las Vegas Hotel -- shared "grievances" in two letters.

The driver, who died before the blast, urged his fellow servicemembers to force Democrats out of government “by any means necessary.”