(JTA) – Allowing hateful terms as options was “a fail on our part,” Facebook CEO Sheryl Sandberg said in a post in which she also defended targeted advertising. Sandberg also announced in the message posted on Facebook last week that the company is strengthening its policies and tools on targeted ads. ProPublica, an investigative website, reported earlier this month that a news website was able to target ads at Facebook users who expressed interest in “Jew hater” and “how to burn Jews.” Facebook removed the categories after being alerted to their existence and said it would seek to prevent such categories from popping up for potential advertisers.

Sandberg wrote in her post: “Seeing those words made me disgusted and disappointed – disgusted by these sentiments and disappointed that our systems allowed this. Hate has no place on Facebook – and as a Jew, as a mother, and as a human being, I know the damage that can come from hate. The fact that hateful terms were even offered as options was totally inappropriate and a fail on our part. We removed them and when that was not totally effective, we disabled that targeting section in our ad systems.”

She defended targeted advertising, which allows companies to place ads based on demographics on the buying history of consumers, or on behavior and self-identification, but said Facebook would clarify its advertising policies and tighten enforcement processes to ensure that content that goes against Facebook’s community standards cannot be used to target ads; by adding more human review and oversight to the automated processes; and by creating a program to encourage users to report potential abuses directly to the company.

Meanwhile, on Sept. 20, Facebook sent out Happy New Year messages to users it believed to be Jewish. But many who received the message weren’t and may have received the greetings because they followed a group with a Jewish theme or posted a message on the Facebook page of a Jewish friend, Mashable reported.