A light has been spotted as emergency workers search for a hiker who has been missing in for a week.

A party looking for Eli Sweeting, 25, from has been focusing on a route heading down Mitre Peak, a steep mountain in Milford Sound area of Fiordland National Park on the South Island, after seeing a light there. However, the area is dense, meaning it is hard for infrared cameras to penetrate and detect signs of movement.

In a statement, his sister Serena Sweeting said earlier this week: "Eli Sweeting has been missing since Sunday, May 4, after failing to return home from a hike up Mitre Peak in New Zealand. There has currently been an incredible effort made by the New Zealand Police, Search and rescue, alpine search and rescue, the real New Zealand and from Milford Sound locals."

In a fundraising post, she added that Eli is one of the "kindest, most compassionate people".

"We just want him home safe," Serena said.

Police said this weekend that there was "large-scale air and ground search effort planned for the coming days".

"While the tramper has not yet been located, police remain positive as the search remains ongoing.

"A Land Search and Rescue team stayed near Mitre Peak overnight to continue the search early this morning."

Local police say they "remain positive" notwithstanding tricky terrain, which has meant they can only progress 250 metres per hour.

Family members have flown out to help, and helicopters, dogs and locals have been deployed to assist.

The search was stopped on Wednesday and Thursday because of warnings of incliment weather, but the operation started again on Friday and Saturday.

Police add that they are hopeful as they know Mr Sweeting is an "experienced hiker".