Twitter has revised its guidelines around abusive behaviour following bomb and rape threats made against several prominent female users of the service in the UK, including MP Stella Creasy and campaigner Caroline Criado-Perez - who campaigned to have Jane Austen on the new £10 note.

"We want people to feel safe on Twitter, and we want the Twitter Rules to send a clear message to anyone who thought that such behavior was, or could ever be, acceptable," Del Harvey, Twitter senior director for trust and safety, and UK General Manager Tony Wang, said at the weekend.

The company is also modifying its interface to make reporting threats and abuse easier. Although users could report abusive behaviour before, Twitter is streamlining that procedure by creating a button within tweets that allows people to file a direct report, the officials wrote.

Users have been referred to Twitter's Help Centre. The button has been introduced in the latest version of Twitter's iOS application and on its mobile site. Next month, the button will appear on its Android application and on, they wrote.

The BBC reported on August 4 that police were investigating eight bomb and rape-related threats made over the social networking service.

A day earlier, Wang said: "I personally apologise to the women who have experienced abuse on Twitter and for what they have gone through."

"The abuse they've received is simply not acceptable. It's not acceptable in the real world, and it's not acceptable on Twitter," he continued.

Twitter also plans to add more staff to its teams that handle abuse reports and is "exploring new ways of using technology to improve everyone's experience on Twitter," Harvey and Wang said.