The brother of a Brit missing in New Zealand says there's footage of the 22-year-old the evening before she disappeared.

Grace Millane arrived in New Zealand about two weeks ago to backpack through the country solo.

When she didn't reply to birthday messages on Sunday, it prompted them to launch a search on social media.

Her older brother Michael Millane says police have found CCTV footage of her returning to her Auckland hostel on Saturday night.

Millane, who'd been in constant contact, stopped responding to messages last Thursday.

Her father is now en route to New Zealand to aide in the search.

He is due to arrive in New Zealand from England tomorrow to help search efforts.

Meanwhile, an Auckland woman swears she saw a girl matching Grace's description near the Southern Motorway in Manukau.