Uber Technologies Inc. is looking into allegations from a former engineer of sexual harassment, a new accusation that is likely to draw renewed attention to the lack of women in Silicon Valley's technical ranks.

Chief Executive Travis Kalanick said the ride-hailing company will conduct an internal investigation in response to a blog post on Sunday by Susan Fowler.

The former software programmer said she was propositioned by her manager and that reports of it were ignored by human resources.

"It was clear that he was trying to get me to have sex with him, and it was so clearly out of line that I immediately took screenshots of these chat messages and reported him to HR," Fowler wrote. She said she was told by senior managers that he was a "high performer" and that they didn't want to punish him for what they considered an "innocent mistake."

Her account is the latest in a series of accusations by women who said they have been sidelined in Silicon Valley's male-dominated culture, especially in engineering roles.

The most visible recent example is Ellen Pao's gender-discrimination lawsuit against Kleiner Perkins Caufield & Byers in 2015. A former engineer at Twitter Inc. claimed a year ago that she was forced out after complaining that men took up a disproportionate number of senior positions in her department. Twitter and Kleiner Perkins, which won the case, denied those claims.

"I have just read Susan Fowler's blog. What she describes is abhorrent and against everything Uber stands for and believes in," Kalanick said on Sunday via a tweet and a statement provided by Uber. "We seek to make Uber a just workplace for everyone 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."

The CEO said he instructed Liane Hornsey, Uber's recently hired chief human resources officer, to "conduct an urgent investigation into these allegations." Arianna Huffington, who is on Uber's board, said she would work with Hornsey on the investigation.

Fowler didn't immediately respond to a message to a Twitter account that appeared to be hers, or an e-mail to the address listed on her website. She said she left Uber in December after a "strange year," and is now working at Stripe Inc., a payments start-up.

In her account on the blog post, Fowler said that she had heard similar stories from other women at Uber, and that some of them involved the same manager.