The fire broke out around 3:45 Sunday morning in the feed lot truck storage area at Harris Ranch, off I5 in Coalinga.
When firefighters arrived the trucks were fully engulfed in flames.
Monday night, Action News received an email from a group called the North American Animal Liberation Press Office.
In it, the organization says it received an anonymous message from someone with very specific details about how the fire was intentionally set.
The group says it doesn't know who specifically sent the message.