Police in Arizona said Wednesday that they had identified a murder victim discovered in 1981 as a missing New Hampshire woman.

Authorities in Tucson said the body of Brenda Gerow was found near the Pima County Fairgrounds in April 1981. Her body was exhumed in 2012 and investigators used her skull to reconstruct her face and identify her. Sheriff's Office Spokesman Tracy Suitt told reporters that investigators have revisited the case over the years and the exhumation was just another attempt to solve the crime.

"It was just taking another step to try to bring this case to a close," Suitt said. "We were trying to figure out who it was for years and years."

Gerow was about 20 when she left Nashua, N.H. with John Kalhauser, a former Massachusetts man who is currently imprisoned for the murder of his estranged wife. Kalhauser had a picture of Gerow with him when he was convicted in that killing, which happened about 15 years after Gerow disappeared, police said.

"It was a photo that showed Brenda sitting down, and she was in an area that looked like it might have been somewhere back East," Suitt said Wednesday.

Based on that, investigators sent the composite photo to several East Coast states. Suitt said once the photo hit social media, law enforcement heard from people who said the person in the image looked familiar. That feedback led to authorities contacting Gerow's family.

Speaking by telephone through an interpreter for people who are hearing impaired, William Gerow told the Associated Press he was overwhelmed by the news of his daughter's death and doesn't know why she was killed.

"We think she ran off, we don't know," he said. "My daughter was just gone and we have no idea why. I don't know what happened. Thirty-three years and still no reason why. Where did she go?"

William Gerow said Arizona detectives visited him about three months ago.

"I really feel blown over by this news," he said.

At this point, Kalhauser is considered a person of interest. Suitt said investigators are hoping to find more people in either New Hampshire or Arizona who may have information. "There's still more investigation that needs to take place," Suitt said.

The conviction in his wife's death was not Kalhauser's first conviction of a violent crime.

In 1996, he was convicted of shooting his ex-girlfriend's boyfriend. Police said Kalhauser followed Michael Renk to a secluded spot in Lowell, Massachusetts, in 1979 after Renk had dropped his girlfriend off at work. Kalhauser was accused of shooting Renk three times in the face and neck.

Kalhauser was arrested and released on bail. He vanished before his next court appearance and spent 15 years on the run, living under the alias Donald J. Stecchi in Tucson, where he was arrested in 1995.

He used a name belonging to a former high school classmate, a deception that was discovered after Arizona police began investigating the disappearance of Kalhauser's wife, who had filed for divorce.