Grace Millane, the British backpacker, died accidentally when consensual rough sex "went wrong", a court has heard.

The defence barrister for the alleged killer told jurors that Ms Millane had a history of engaging in choking during sex and had been a member of a BDSM (bondage, discipline, dominance and submission) websites.

Police said that Ms Millane, 21, had been active on BDSM dating site Whiplr an hour before meeting the defendant outside a casino in Aukland's city centre.

The defendant, 27, who cannot be named for legal reasons, met Ms Millane on a Tinder date. He says she died after she asked him to put his hands on her neck during rough sex.

He initially denied being involved in her death but later told police she died in his flat, where he "panicked" before cramming her body into a suitcase which he buried in a shallow grave in the woods.