Firefighters are battling a massive six-alarm blaze that investigators believe was intentionally set in San Bernardino County early Tuesday morning. Multiple agencies responded around 12:30 a.m. to a fire reported at the approximately one-million-square-foot Kimberly-Clark warehouse near South Hellman Avenue and Merrill Avenue in Ontario.

Fire crews responded to the Kimberly Clark Warehouse in the 9500 block at the Merrill Avenue at 1:45 a.m. and found the approximately one-million-square-foot warehouse ablaze.

No one was killed or injured in the fire in Ontario, Calif., but a gigantic building was destroyed in an act of arson, officials said.