Police search and rescue teams have converged on a an area of bush at a West Auckland beach after an item that could be linked to a missing French teenager was found there.
Eloi Jean Rolland, 18, came to Auckland as part of a student exchange programme in September.
He was staying with a host family in Birkenhead on the North Shore and failed to return home on March 6.
Police later confirmed the last sighting of Rolland was the next morning.
At about 6.30am he was captured on CCTV footage catching a train from Britomart Station in the CBD.
At 7.26am he exited Fruitvale Station at New Lynn.
Cell phone data picked up later placed the teenager in the area of Piha Rd at 9.18am.
Police believe he may have walked there - a journey of at least 10km.
Rolland has not been seen since.
Police confirmed today that a T-shirt was found in an area of bush at Karekare last weekend.
"It is being forensically tested and police are keeping an open mind as to whether it may be linked to the search for Eloi Rolland," said Detective Senior Sergeant Callum McNeil.
"Search and rescue personnel have returned to the area to see if there are any other items of interest."
Meanwhile, Rolland's family have made a desperate plea to their own authorities for help.
"We would like there to be collaboration between the French police and the New Zealand police," his sister Aurore told BFMTV.com
"The latter asked for it but with the coronavirus crisis, France refused.
"We understand that there is a health crisis, but we would just like the French police to question us - they may have relevant questions that we have not thought of.
"We must do our utmost so that the search continues."
His family in France are devastated that they cannot travel to New Zealand to search for him themselves.
The global Covid-19 pandemic means they cannot travel here.
Rolland's cousin Segolene said New Zealand authorities had told the family they'd requested help from their French counterparts and Interpol.
However, due to the pandemic, they were limited.
Rolland's mother had also written to French President Emmanuel Macron.
"A senator replied that a conference call would be organised, but we never [heard] back,"
Segolene told French publication Le Parisian.
"We are abandoned, we feel helpless and we have no information about his disappearance.
"The idea of not being able to go there to help with research is very hard to manage."
Rolland had told his family he was homesick and decided to return home months earlier than originally planned.
His return ticket was scheduled for late May but he was set to head back to Montpelier in Southern France, on May 21 .
Segolene said time was "running out" and her family were frantic.
"The chances of finding him alive are increasingly slim," she said.
Police in Auckland are still investigating Rolland's disappearance and say they are in regular contact with his family.
When Rolland left his Birkenhead homestay he took some belongings but did not say anything about his plans.
It is not known what he did the night before he left Britomart.
His cellphone stopped transmitting shortly after 9am in the middle of the road in an area
he had visited previously with friends.
Police searched the area but there was no sign of the teenager.
Officers even asked the owners of vacant homes in the area to check whether Rolland was there.
Segolene told Le Parisian that the Rolland family had many questions about the strange disappearance and continuously went over different scenarios about what could have happened.
Rolland had a "passion" for hiking and they wondered if he had an accident out on a track.
"We thought of everything, the voluntary disappearance, of course, the accident too," Segolene said.
"But after a month, I tell myself that it is not possible.
"We would have found his body if that was it.
"We are more and more convinced that something strange happened, that he had a bad meeting."
Detective Senior Sergeant Callum McNeill said police were keeping an open mind around
what has happened to Rolland.
"But as each day passes, the chances of finding Eloi alive and well are sadly becoming more slim," he said.
"This has been an incredibly difficult time for his family in France and we are supporting them as best we can.
"We continue to do everything we can to find Eloi and provide his family with answers to the questions they desperately seek."
Last month Rolland's family issued a statement through the police.
"Eloi's disappearance worries us greatly and every day that he remains missing only causes us more concern," they said.
"Eloi is a calm, kind and curious teenager who loves adventures and enjoys being with friends.
"He loves the sea, surf and catamarans. He also enjoys the beauty of the wilderness and recently found a particular interest in hiking."
Before his disappearance, Rolland was in regular contact with his family several times a week.
"His disappearance is very out of character and we are extremely worried," they said.
"He has never run away from home.
"Recently Eloi became homesick and wanted to return to France and study at university.
"We haven't heard from him since he went missing on March 7th.
"We desperately want to know where Eloi is and we urge anyone with information or any sightings of him to please contact police."
Anyone with information is urged to contact Waitemata Police on 09 839 0697.
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