"In light of these actions, not promoting him was definitely the right move".
On Monday, it emerged that a fire had been discovered in a Fremont, California-based plant the previous day, forcing production to stall. While he says this could be a random event, Musk quotes former Intel CEO Andy Grove's "Only the paranoid survive" warning.
CNBC managed to obtain Musk's entire email revealing the saboteur, which you can read in full.More news: Manchester United set record breaking price for Martial
A Tesla spokesperson declined to comment when asked by Fox News if the matter has been referred to outside law enforcement.
The Tesla CEO's messages to employees come days after some 3,000 Tesla employees were dismissed, representing almost a tenth of the entire workforce.
The problem erupted as Tesla races to increase auto production to meet a goal of producing 5,000 of the company's Model 3 vehicles per week by the end of June - a goal Musk told shareholders on June 5 that the company was "quite likely" to achieve.More news: Saudi Arabia's plane catches fire on way to World Cup game
Musk thanked departing staff for their service, saying the company was "making this hard decision now so that we never have to do this again"; he also promised Tesla would "continue to flatten" its management structure.
A disgruntled worker taking out their anger on an employer isn't unusual, but Telsa and Musk are investigating whether this person was working with outside entities, such as "Wall Street short-sellers" or "oil & gas companies".
Musk said the reorganisation did not affect hourly-paid assembly-line employees and was not expected to delay manufacturing targets. He claims that while these companies cheat about emissions, maybe they can cheat in other ways.
Elon Musk personally took over supervision of Model 3 production in April after multiple setbacks caused by manufacturing issues.More news: Back-to-back US Opens for Koepka
A Tesla employee has been carrying out "extensive and damaging sabotage", according to the company's chief executive. "They have about three weeks before this short position explodes", Musk wrote.