The father of missing US tourist Carla Stefaniak has confirmed that a body found near a Costa Rica Airbnb is that of his daughter.

Her family confirmed the identification in a Facebook post, saying words could not express their devastation.

Ms Stefaniak disappeared on 28 November during a trip to celebrate her 36th birthday.

A security guard who had been staying in the room next door to Ms Stefaniak was arrested on Tuesday.

The Nicaraguan suspect, named as 32-year-old Bismarck Espinosa Martinez, made conflicting statements to police, according to officials.

His arrest came a day after investigators found a woman's body partially buried and covered in plastic bags near the Airbnb villa in San Jose.

The body had suffered stab wounds and a blow to the head, police said.

In a statement on Facebook, her family said: "Words cannot express the devastation within her family and friends. We want the world to know that we will never forget Carla."

Ms Stefaniak's family had travelled to Costa Rica to search for her, fearing she had been kidnapped.

Ms Stefaniak, from the Miami Beach area of Florida, and her sister-in-law April Burton were visiting Costa Rica to celebrate Ms Stefaniak's birthday, but Ms Burton returned to Florida a day before Ms Stefaniak.

The last time Ms Burton saw Ms Stefaniak was when she left her at the airport on 27 November.

Ms Stefaniak then reportedly took an Uber from the airport to do some sightseeing around San Jose before she was dropped off at the Airbnb.

She had been actively messaging friends and family throughout the day.

Her final text to a friend around 21:00 local time indicated it was raining hard and the power in her Airbnb accommodation had gone out.

Family and friends texted Ms Stefaniak for her birthday on 28 November, but received no response.

Ms Stefaniak had a flight scheduled for the following day, for which she had checked in, and she had booked an Uber.

But her family later learned she never boarded the flight home.

The Airbnb rental owner and local security guards said they saw her get into an unknown car with her luggage at around 05:00 local time, according to the family.

"None of us really believe this 5am story because it really doesn't make sense," Ms Burton told Fox News.

"There's no reason for her not to contact anyone."

According to the family's Facebook page, officials had initially not pursued the matter because Ms Stefaniak had appeared "rational at the time of her disappearance and got into a taxi of her own free will".

An Airbnb spokesman said the company had contacted Ms Stefaniak's family, as well as law enforcement authorities, to support and co-operate with the investigation.

The US Embassy in Costa Rica said it had no comment to give on the investigation.