Police are continuing to investigate the disappearance of missing 22-year-old English tourist Grace Millane.
Ms Millane's father, David Millane, 60, a millionaire property developer, is in the process of flying to New Zealand to help with the search.
"Grace has been missing for 5 days", her brother Michael Millane posted on Facebook on Tuesday.
Mr Beard said none of her roommates at the backpackers were with her on Saturday evening and there was sufficient evidence to suggest she was going to go back to the hostel to collect the items she had there.
He urged anyone who has seen Millane or knows her to contact police.
Detective Inspector Scott Beard this afternoon said her disappearance was "out of character", after her family in the United Kingdom raised the alarm on Monday.
Her older brother said it was completely out of character for her not to be in contact with her family.
"The longer this goes on, the more worrying it is".
"We are asking anybody who has been in contact with her or knows her to contact police". She's approximately 5ft 6in (168cm) in height, and 58kg.
Mr Beard said Ms Millane had a number of phones on her while in New Zealand.
The Foreign Office said it was providing support to Auckland police.
Image Ms Millane who turned 22 on Sunday arrived in the city two weeks ago
Ms Millane is said to have been in New Zealand for about two weeks, and was staying at a backpackers' hostel in Auckland city centre.
He added that she had travelled to Peru as part of an organised group for six weeks but had not travelled on her own until she arrived in New Zealand two weeks ago.
A number of unconfirmed sightings have been reported to officers.
It was her first time travelling solo.
"In the CCTV image Grace is seen wearing a black dress and white shoes, believed to be Converse shoes".
Declan Millane said a few people had reached out to the family with potential sightings.
Grace Millane, 22, had been backpacking around the country and was last seen in Auckland on Saturday night.
Grace Millane, who is from Essex, has been reported missing by her family, who say they have not heard from her in almost a week.
Base Backpackers were approached by Stuffon Wednesday but declined to comment.
"She hasn't really replied to any messages between the family and it was her birthday on Sunday and she didn't respond to any messages".
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