Twitter has revealed better-than-expected sales and profits in the three months to September 30.

The social network beat analyst expectations for the quarter, sending shares up 13% in pre-market trading.

Jack Dorsey, the group’s CEO, said in the earnings release: “We’re achieving meaningful progress in our efforts to make Twitter a healthier and valuable everyday service.”

“We’re doing a better job detecting and removing spammy and suspicious accounts at sign-up. We’re also continuing to introduce improvements that make it easier for people to follow events, topics and interests on Twitter, like adding support for U.S. TV shows in our new event infrastructure. This quarter’s strong results prove we can prioritize the long-term health of Twitter while growing the number of people who participate in public conversation.”

Revenue increased by 29% to $758 million.

The total number of users on Twitter fell due to the social media platform’s crackdown on “spammy and suspicious” accounts.

The group said earlier this year that it would look at “behavioural signals” to “improve the health” of discussions on the platform.

“People contributing to the healthy conversation will be more visible in conversations and search,” it said.

“These accounts have a disproportionately large – and negative – impact on people’s experience on Twitter.”

“The challenge for us has been: how can we proactively address these disruptive behaviours that do not violate our policies but negatively impact the health of the conversation.”

In the first three months of 2018, the media group deleted 29 million posts that broke rules on hate speech, graphic violence, terrorism and sex.

Shares in the group (NYSE: TWTR) are trading +17.32% at 32,31 (1454GMT).