SpaceX fired employees on Thursday who helped write an open letter criticizing CEO Elon Musk's tweets and other recent behavior, according to the New York Times.

Why it matters: Musk is currently attempting to acquire the social media platform Twitter in what he has said is an effort to create a haven for free speech. Musk has repeatedly said that open discussion and debate is necessary for society and democracy to function.

What they're saying: In the open letter, which was first published by The Verge on Thursday, employees wrote that "Elon’s behavior in the public sphere is a frequent source of distraction and embarrassment for us," referring to recent sexual misconduct allegations against the billionaire that he has denied and his recent tweets.

• "As our CEO and most prominent spokesperson, Elon is seen as the face of SpaceX — every Tweet that Elon sends is a de facto public statement by the company," the letter reads. "It is critical to make clear to our teams and to our potential talent pool that his messaging does not reflect our work, our mission, or our values.”
• Among other requests, the employees asked SpaceX's executive team to "publicly address and condemn Elon’s harmful Twitter behavior," saying, "SpaceX must swiftly and explicitly separate itself from Elon’s personal brand."

The other side: Gwynne Shotwell, SpaceX’s president and COO, said in an email to employees on Thursday first obtained by the Times that the company investigated and "terminated a number of employees involved" with the letter, though it was unclear how many employees were fired.

• Shotwell claimed in the email that "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."
• “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," she added.
• The Verge, which also published Shotwell's email, reported that employees were being encouraged by other employees to sign onto the letter either publicly or anonymously.
• A SpaceX spokesperson did not immediately respond to an email seeking additional information about the situation Friday.

Go deeper: Musk takes heat from Twitter employees at town hall