NEW YORK (REUTERS) - Twitter removes more than a million spam accounts each day, executives told reporters in a briefing on Thursday (July 7), providing new insight into efforts to reduce harmful automated bots as billionaire Elon Musk has demanded more details from the social media company.

The briefing comes after Musk threatened to halt a US$44 billion (S$60 billion) deal to purchase Twitter unless the company showed proof that spam and bot accounts were fewer than 5 per cent of users who see advertising on the social media service.

Musk previously tweeted that one of his biggest priorities after acquiring Twitter is to "defeat the spam bots or die trying."

On a conference call, the company reiterated that spam accounts were well under 5 per cent of users who are served advertising, a figure that has been unchanged in its public filings since 2013.

Human reviewers manually examine thousands of Twitter accounts at random and use a combination of public and private data in order to calculate and report to shareholders the proportion of spam and bot accounts on the service, Twitter said.

The company said it does not believe a calculation of such accounts could be performed externally because it would require private information, but declined to comment on the type of data it would provide to Musk.