A physical therapist vanished in a Hawaii forest. Days later, there's still no sign of her

Amanda Eller went missing in Maui last week. A massive search is underway to find her. Photo / Facebook

Before she vanished last week, Amanda Eller parked her white Toyota RAV4 and, readying for a hike in a sprawling Maui forest, left her phone and wallet in the car and her key on the tyre.

Police found Eller's car and belongings but, days later, have found no sign of Eller.

Hundreds of volunteers have combed through the dense Makawao Forest Reserve looking for Eller, 35, as officials scaled back their search.

Julia Eller spent Mother's Day preparing for a flight to Maui to join the search for her daughter, which resumed today.

"Please, please, hold on, Amanda. I'm coming," she told KITV 4. ". . . We still have history to make together, and I need you as part of my life."

The family has offered US$10,000 for information that leads to her safe return, AP reported.

Since her disappearance, authorities dispatched tracking dogs, helicopters and drones to scour the forest on the northern side of Maui, which were joined by hundreds of volunteers marshaled for the search.

Maui fire officials wound down their search efforts in the air and by foot after reaching their 72-hour limit for assisting in missing persons incidents, KHON reported, but will aid police if there are any new developments.

The forest has bedeviled volunteers who faced the difficult terrain, thick with creeks, ravines and brush. Volunteer coordinators have pleaded for hunters and experienced climbers to search the most challenging regions of the forest, Maui News reported.

Volunteers have prepared for all possibilities as they escalate the search.

"Generally speaking, it's highly likely she's lost or injured in this forest and it's equally as likely that she was intercepted by someone in the parking lot or on her run," friend and volunteer Sarah Haynes told Maui News.

"As the days go by, and more and more people are in the forest, we get closer and closer to foul play."

Eller, who lives outside the reserve in Haiku, is a physical therapist. But her deep ties as a yoga instructor on the island have propelled volunteers to join the search effort.

"Amanda's really well loved in the yoga community and there are people coming from all over the island coming in and hiking and trying to find her," Haynes told CNN.