The motive, according to the Daily Mail, may have been that one of the men stole a teabag belonging to another.
Although, the two men had apparently worked with each other previously, so there may also be history there.
The attack took place at the Warner Bros. studio located in Leavesden, Hertfordshire where the remake of The Witches, based on the book by Roald Dahl, is currently shooting.
Yesterday afternoon a stagehand was allegedly stabbed in the neck by a rigger.