Updated

As the FBI joins the investigation, Turkish authorities have completed the autopsy on the Latina found dead in Istanbul.

On Monday, the country’s state-run media reported that DNA samples had been submitted on the remains of Sarai Sierra, the 33-year-old Puerto Rican mother of two who went missing Jan. 21 while on a solo vacation. Her body was found 12 days later, near the remnants of some ancient city walls.

Police said Sierra suffered a fatal blow to the head and that authorities were still scouring the area where the body was found for clues, with the help of sniffer dogs, the state-run Anadolu Agency reported.

The Milliyet newspaper said a forensic medicine lab will examine samples from Sierra's fingernails as well as hair and other samples from a blanket found near her body. It said some nail scrapings suggest she may have tried to fight off her attacker.

More than a dozen people were questioned in the case but most of them have been released, Milliyet reported. It said three people were still being held for questioning.

The office of U.S. Rep. Michael Grimm (R-NY) has been in constant contact with officials overseas throughout the search for the missing Staten Island resident.

A former FBI agent, Grimm has played a significant role in the investigation into the death of Sierra.

"Our community mourns the loss of a beloved wife, daughter, and mother of two children; as we are deeply saddened to hear the news of Sarai Sierra’s death," Grimm said during a press conference in Staten Island.

Grimm and Sierra's parents, Betzaida and Dennis Jimenez, say the family's immediate concern is returning Sierra's body to the U.S.

Sierra's husband, Steven, is still Turkey. He intends to accompany her body, but the family is still trying to figure out how to fund the transport.

Sierra, whose children are 9 and 11, had left for Istanbul on Jan. 7 to explore her photography hobby and made side trips to Amsterdam, Netherlands and Munich, Germany. She was to have traveled with a friend, but the friend cancelled.

Sierra's mother, Betsy Jimenez, said her two grandsons did not know what had happened to their mother.

"Their father is going to talk to them when he comes back and we'll all be there to support him," she told NBC's Today show on Monday

Jimenez said it was Sierra's first overseas visit.

"She wanted to go take pictures of the history of the place... and she was interested in taking pictures of the bridges. She was fascinated with the bridges," Jimenez said.

Maggie Rodriguez, a friend of Sierra's who was supposed to accompany her on her trip to Turkey, told the Staten Island Advance that she feels guilty because her friend might still be alive if she had traveled with her.

"If I went with her, maybe this wouldn't have happened," said Rodriguez, who backed out of the trip because of financial reasons. "Maybe we would have went to a different spot that day. Maybe we'd be sitting in a cafe, just chit chatting with each other."

The Associated Press contributed to this report. 

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