Police are now treating the disappearance of 17-year-old Pheobe Bishop as suspicious, nearly a week after she was last seen.

Pheobe was last spotted about 8.30am on May 15 on Airport Dr in Bundaberg, a regional city in Queensland.

She was due to board a booked flight from Bundaberg Regional Airport but never made it to the terminal, police confirmed after reviewing the CCTV footage.

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She has not been seen or heard from since, with her family describing her disappearance as being out of character.

The home in Gin Gin where Pheobe was staying before she went missing and a car she is believed to have travelled in are now crime scenes, police said on Wednesday.

The car, a grey Hyundai ix35 with Queensland registration 414EW3, has been seized by police who are now appealing for information on its movements.

Officers are urging anyone with dashcam or CCTV footage of the car near Airport Dr and Samuels Rd in Bundaberg, or in the Gin Gin area on May 15, to contact police immediately.

Detective Acting Inspector Ryan Thompson on Wednesday said Pheobe had been living with two people she had known for some time, who are not direct family members.

Police believe the seized car belongs to one of the people Phoebe had been living with, and they are investigating the timeline of her journey.

Thompson added officers are speaking with the person she was meant to visit in Western Australia.

A family member told The Daily Mail she had saved up to purchase the airfare herself to see her boyfriend.

“He was her high school sweetheart that moved away,” they said.

Another relative told the outlet Pheobe was on the phone with her boyfriend not long before she disappeared.

”She didn’t check in for her flight to visit her boyfriend who she spoke to on the phone at 8.30am,” they said.

“Her phone has been switched off from this point. She hasn’t contacted anyone at all, no one has seen her.”

Pheobe is described as being about 180cm tall, with a pale complexion, long dyed red hair and hazel eyes.

At the time of her disappearance, she was wearing a green tank top and grey sweatpants, and was carrying luggage that has yet to be found.

Her worried family has been posting daily on social media in the hope someone comes forward with information.

“As we enter another day with Pheobe still missing our hearts are breaking more and more,” Pheobe’s mother Kylie Johnson wrote.

“Phee we just need to know that you’re OK? We just need to hear your voice.

“Right now we are grasping onto hope and just trying to breathe.”

The family has put up 400 posters across Bundaberg, Bargara, Childers, Biggenden and nearby towns, and have been searching bushland and the nearby river around the airport with the help of volunteers.

Johnson thanked the community and police for their support, and urged people to keep spreading the word.

“All we need as a family is for you guys to keep sharing Pheobe’s QPS poster,” she said.

“The more people we reach, the more people ... are looking for the baby of our family.

“We as a family are holding onto every bit of hope that our daughter, sister, aunty, niece, cousin and imperative member of our family comes home soon.”

Johnson said as well as her daughter’s sudden communication silence and lack of social media activity, there have been no bank transactions made since Wednesday.

She said this was unusual because Pheobe “spends money like water”.

Johnson dismissed speculation her daughter ran away, saying Pheobe “would never leave her family without contact”.

“We are lost at what to do next and people keep asking has she run away,” Johnson said.

“If you knew Pheobe you would know that she is free spirited and loves hard.

“She is loyal to the core.”

Police are urging anyone with information about Pheobe’s whereabouts to come forward.