SpaceX has fired employees who participated in writing and distributing an open letter criticizing Elon Musk, The New York Times has reported. First revealed yesterday, the letter called Musk's behavior on social media "a frequent source of distraction and embarrassment" and asked SpaceX to condemn his actions.

According to three unnamed employees and an email from SpaceX president and COO Gwynne Shotwell seen by the NYT, SpaceX fired some of the letter's organizers, but there's no indication of how many were let go.

"[SpaceX has] terminated a number of employees involved" with the letter, she wrote. "The letter, solicitations and general process made employees feel uncomfortable, intimidated and bullied, and/or angry because the letter pressured them to sign onto something that did not reflect their views. We have too much critical work to accomplish and no need for this kind of overreaching activism."

The open letter from the employees referenced recent accusations of sexual misconduct involving Musk that reportedly prompted a $250,000 settlement. Musk said the allegations were "utterly untrue" and made a crude joke about some of the details on Twitter. SpaceX defended Musk, with Shotwell saying she "personally" believed the accusations were false.

Another subject in the letter was distractions due to Musk's Twitter use. In February, the SEC opened an investigation into Musk over possible insider trading, and a court recently ruled that Tesla company lawyers must continue to approve his tweets. (Earlier this week, Musk appealed that decision). Prior to the letter, Musk reportedly told SpaceX employees that they must spend at least 40 hours a week in the office or risk being fired.

In her email, Shotwell added that "blanketing thousands of people across the company with repeated unsolicited emails and asking them to sign letters and fill out unsponsored surveys during the work day is not acceptable. Please stay focused on the SpaceX mission, and use your time to do your best work. This is how we will get to Mars."

Employees are protected against retaliation by OSHA's whistleblower rules, but those generally apply to issues like safety, fraud, environmental issues and health insurance. Still, the firings are likely to create another round of controversy involving Musk.