Twitter boss sorry over white supremacist ad

Twitter chief executive Jack Dorsey has apologised after an advert for a white supremacist group appeared on the social media platform.

The advert promoted an article headlined, "The United States was founded as a white people's republic."

Mr Dorsey tweeted that the firm had "made a mistake" and blamed an automated system.

However, according to reports, Twitter had originally said a screenshot of the advert appeared to be fake.

When the ad was first brought to Twitter's attention by writer and musician Ariana Lenarsky, a spokesperson told the website Motherboard that the screenshot she provided looked "either old or photoshopped".

Ms Lenarsky said she would leave the site until the firm apologised.

"Acknowledgement from [Jack Dorsey] & [Twitter] is great, but it really isn't over," she has now tweeted.

"We must continue to hold feet to the fire on this stuff."

The Twitter account of the group behind the ad, known as New Order, has now been suspended.

Last year, a right-wing activist claimed he had been able to promote a tweet which began "whites need to stand up for one another" using Twitter's advertising tools to target specific users, reported Slate.

This week Twitter announced new tools for tackling abuse, which includes hate speech, on its platform.