Relatives of an Iranian Press TV reporter, a US national killed in a suspicious car accident in Turkey, claim they have received no support from US authorities during the investigation, which is full of many inconsistent details.

Serena Shim, a US citizen, was killed in a car crash on October 19, following her reports of accusations from Turkey’s intelligence agency that she had been “spying.” She had been covering the crisis in the besieged Syrian city of Kobani. Press TV channel called the accident "suspicious."

Shim’s sister said the family received inconsistent reports about the death.

“There are so many different stories. The first story was that Serena’s car was hit by a heavy vehicle who proceeded to keep on driving,” Fatemeh Shim told RT.

She added that Turkey couldn’t find the vehicle nor could they find a driver.

“Two days later, surprisingly they [Turkish authorities] have found the vehicle and the driver and had pictures of the heavy vehicle heading my sister’s car.”

Fatemeh says every day her family comes “with new pictures of different degrees of damages that have happened to the car.”

“Serena and my cousin, who was the driver of the car, were taken to different hospitals. She was reported first dead at the scene, then later reports said that she passed away at the hospital 30 minutes later from heart failure. It’s just very confusing.”

Fatemeh says both she and Serena are US citizens, and were born and raised in America, but she feels they “have got no support, nor have we got condolences.”

RT requested a comment from the Turkish authorities, but we are yet to receive an answer.

RT's Gayane Chichakyan asked a US State Department spokesperson if there is any update on the death of a US citizen and journalist under unclear circumstances.

Jeff Rathke replied, “[we] don’t have any information to share at this time."

RT also obtained a personal message from Serena to her mother, which was one of her final recordings.

“Being killed is scary, Mom…going to jail is not scary. It sucks, but it’s not scary,” she said in the audio message.

In the meantime, the office of the Representative on Freedom of the Media at the OSCE told RT that Turkey is carrying out an investigation.

“The representative has been following the case since the first reports appeared about the car accident that claimed the life of journalist Serena Shim. According to information available to her office, the Turkish authorities have started investigation into the details of the car accident,” said Gunnar Vrang, from the office of the OSCE Representative on Freedom of the Media.

Shim, who left behind two children, a two-year-old daughter and a four-year-old son, had expressed fears for her own safety, a day before her death she reported receiving threats from the Turkish intelligence agency (MİT), saying they had accused her of spying.

“I’m very surprised I’m even thought about approaching… As you know Turkey has been labeled by Reporters Without Borders… frightened by what they might use against me,” she said on the recording from October 17.

Shim had been reporting that IS militants had crossed the border from Turkey into Syria in trucks apparently affiliated with NGOs, some of which allegedly bore World Food Organization symbols. She claimed that she had received images from Islamic State militants crossing the Turkish border and was one of the few reporters focusing on the matter.