Just days after billionaire Elon Musk announced that his health tech company, Neuralink, is expected to start human trials for its brain chip in the next six months, the firm has been accused of welfare violations. Animal tests being conducted at the company are conducted to the deaths of 1,500 animals across four years, allegedly breaching welfare guidelines.

The tests are centered around Neuralink’s work on developing a brain chip that will hopefully help paralyzed people learn to walk again. News agency Reuters has seen a report alleging that hundreds of sheep, pigs, and monkeys have died following experiments since 2018, coupled with claims from employees at the company describing needless suffering and deaths.