The family of a Florida woman found dead near her vacation rental in Costa Rica has filed a lawsuit against Airbnb and the resort where she was staying.

The lawsuit was filed Thursday in Hillsborough County, Florida, and accuses Airbnb, Inc. and the Villa le Mas resort of failing to conduct a background check on a security guard who was in the country illegally.

Authorities arrested the security guard, Bismarck Espinosa Martinez, earlier this month after they said his story "demonstrated a lot of inconsistency." Martinez, 32, was not immediately charged after his arrest.

Walter Espinoza, director general of the investigative agency in Stefaniak’s case, said Martinez was a Nicaraguan immigrant who entered Costa Rica in June.

Stefaniak’s family said in the suit that Martinez "lacked documentation and legal authorization" to be employed in Costa Rica and also did not have the proper documentation to be in the country.

Carla Stefaniak via Facebook

The family also alleged that Airbnb and the resort in San Antonio de Escazu, west of the capital of San Jose, "negligently failed to perform any kind of background check” on Martinez.

"Our hearts are broken for Carla’s family, friends, and loved ones," Airbnb said in a statement to NBC News. "We reached out to provide support to them during this unimaginably difficult time. We have also been in contact with Costa Rican and American law enforcement authorities, and we are standing by to support their investigation, as justice must be served quickly."

The Costa Rican resort could not immediately be reached for comment.

Stefaniak, of Hallendale Beach in Broward County, had traveled to the Central American country with her sister-in-law to celebrate her 36th birthday. She was last heard from on Nov. 27 when she told her friends that it was raining and the power had gone out in her rental.

In a text message via WhatsApp, Stefaniak had told friends that things were "super sketchy," according to a timeline of events that people close to the investigation previously provided to NBC News and is in the lawsuit.

And in a FaceTime call with another friend, she said that she was going to ask a security guard at the rental to get her some water because the weather was still bad, according to the timeline.

Her family reported her missing after she failed to board her flight home on Nov. 28.

One of her brothers, Mario Caicedo, told NBC News that a body found behind the rental was his sister’s. Costan Rican investigators said the body was discovered partially buried in plastic bags.

An autopsy found that the body had stab wounds in the neck and other areas, as well as injuries consistent with having been hit in the head.

The family said in the lawsuit that they believe multiple people were involved in removing and disposing Stefaniak’s body. They are seeking damages "in excess of $15,000" from the resort and Airbnb.