On Sunday afternoon, Susan Fowler — now an engineer at payments company Stripe — published an essay alleging that Uber’s human resources representatives ignored multiple reports of sexual harassment and sexism during her year-long stint at the company.

In response to her essay, calls to #deleteUber — a hashtag that gained steam when people thought the car-hailing service was trying to profit off the backs of taxi drivers protesting President Donald Trump’s travel ban — have cropped up on Twitter again. Uber CEO Travis Kalanick stepped down from a Trump advisory council in part due to the vehement response to the widespread complaints.

The #deleteUber movement hit the business hard, with Uber reporting over 200,000 account deletions, although other sources said the number was even higher.

Now this new controversy — especially since Uber has previously been criticized about its commitment to the safety of female customers, some obviously sexist ads and also several very questionable comments from its top execs related to women — has the potential to make those numbers rise even further.

So it’s no surprise that Kalanick responded quickly to the Fowler essay on Twitter. “I have just read Susan Fowler's blog. What she describes is abhorrent and against everything Uber stands for and believes in,” wrote Kalanick, who claimed it was the “first time this has come to my attention.” “We seek to make Uber a just workplace and there can be absolutely no place for this kind of behavior at Uber — and anyone who behaves this way or thinks this is OK will be fired."

He also said the company’s recently hired head of human resources, Liane Hornsey, will be launching an “independent” investigation into Fowler’s claims, along with independent board member Arianna Huffington.