A nonprofit physicians organization has sent a letter to top government officials alleging that Elon Musk made false claims that at least a dozen monkeys who died during Neuralink brain implant experiments were “terminally ill,” according to news.

The Physicians Committee for Responsible Medicine (PCRM), after obtaining documents via a public records request and lawsuit, formerly alleged that Neuralink had violated federal animal welfare laws and killed at least 1,500 animals in its brain implant experiments — sparking a federal investigation that remains ongoing.

Those alleged victims included at least a dozen macaques who reportedly suffered and ultimately died from complications, including brain swellings and infections.

Musk took to his platform X, formerly known as Twitter, in September to deny those allegations, instead claiming that the monkeys who died all were “terminally ill.”

Neuralink and Musk did not respond to media inquiries.

But in the post from Sept. 10, which has since been archived on the Way Back Machine, Musk wrote, “No monkey died as a result of a Neuralink implant. First our early implants, to minimize risk to healthy monkeys, we chose terminal monkeys, close to death already.”

The letter from PCRM, which asks officers with the U.S. Securities and Exchange Commission to investigate and penalize Musk and Neuralink, provides examples of documented animal suffering that appear to directly contradict those claims. 

“Public records obtained by the Physicians Committee reveal that at least 12 young, previously healthy monkeys were euthanized by Neuralink as a direct result of the company’s implant,” the letter reads. “The animals deaths and the reasons for their deaths relate directly to the safety and marketability of the brain-computer interface Neuralink is developing, and thus it is critical that the company provide investors with factually accurate information.”

The letter notes that captive macaques typically can live to be between 25 and 40 years old and that at least 10 of the 12 monkeys who died in the Neuralink experiments were less than 8 years old — meaning they hadn’t even reached adulthood.

The letter summarizes the deaths of four monkeys, including “Animal 22,” a 6-year-old male macaque whose implant screws reportedly loosened to the point where lab staff could lift them out due to a “purely mechanical” failure.

Meanwhile, Neuralink has announced that the Food and Drug Administration (FDA) has approved human clinical trials of the brain implants and that the company is actively recruiting people who suffer from paralysis, with an aim to see if they can control a computer keyboard or cursor with their thoughts.

It’s unknown how many people may enroll in the study, according to Reuters, which also reported that Neuralink initially had requested 10 people but was negotiating a lower number with the FDA.

We thank the more than 35,000 people who have signed our petition urging authorities to thoroughly investigate Neuralink for violations of the federal Animal Welfare Act. If you haven’t already, please take action for defenseless animals in laboratories today by signing and sharing our petition!

SIGN: Stop Deadly Animal ‘Brain Machine’ Tests at Elon Musk’s Neuralink