HOUSTON -

A private investigator said he has found evidence that links a man who has confessed to killing a college student to the 2010 disappearance of a Spring teenager.

Thousands of volunteers rallied to find missing college student Mickey Shunick in May 2012. But months after she disappeared, a man confessed to her murder.

NBC News in profiling that case on a special Dateline Tuesday Night on KPRC Local 2, but the story might not end there.

"There is so much tying into Ali," said private investigator Mac Sanford. "It's just difficult to over look it."

Sanford is convinced a man who killed two women in Louisiana has other victims, among them a 16-year-old Spring high school student.

Ali Lowitzer vanished in April 2010.

"We have him within one mile of Ali's house the day she went missing," said Sanford.

Sanford said he has presented a mountain of evidence to investigators from Houston to Louisiana trying to convince them Brandon Laverne, a man already in prison serving a life sentence for two murders, was in the area the same day Lowitzer vanished.

"His vehicle that he was driving matched the description of a vehicle on our tip line when Ali originally went missing," said Sanford.

But Sanford admits that lead on the tip line does have its flaws.

The guy who wrote down the plate number accidentally discarded the clue a week later.

"So they put him under hypnosis and that's where we got a partial of what Laverne was driving at the time," Sanford said.

Sanford has put a lot of work into this case, but a Harris County sheriff's investigators said he's off track and there is nothing that ties Brandon Lavergne to Ali Lowitzer, and Louisiana law enforcement officers agreed.

"They called me and said I'm on the wrong path, and I have my facts mixed up," Sanford said. "I don't have my facts mixed up."

Sanford said he's not just hanging his hat on the idea Lavergne snatched Lowitzer.

"Every lead is worth following up. We have to follow up every lead," Sanford said.

He's now looking into a tip that Lowitzer is alive and was spotted recently in Juarez.

So Sanford's next stop is Juarez, Mexico. It's a new lead and a new chance to solve a mystery.

Slideshow: Ali Lowitzer

Published On: Jul 27 2010 06:23:53 AM CDT   Updated On: Jul 27 2010 06:25:34 AM CDT

Ali Lowitzer has been missing from Spring since April 2010. Take a look at some photos of her and please call police if you've seen her.

Ali Lowitzer
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