ST PETERSBURG, Fla. - Every year there are 4,400 unidentified persons cases in the United States.

Investigators work hard to close each one, but for families with missing loved ones, it's a very difficult road to navigate.

That's where a system called NamUs comes into play.

It's a searchable database where descriptions of unidentified or missing persons are entered by medical examiners and law enforcement agencies across the country.

NamUs, which was created 10 years ago, has played a role in closing 99 missing persons cases and 70 unidentified persons cases in Florida. Many law enforcement agencies across the state use the database to enter information about missing or unidentified persons. Some states, including New York, Connecticut and Tennessee, have laws requiring agencies to utilize NamUs.

Detectives enter the information they have, including gender, race, age, height even dental records, into the database. They also enter things like tattoos, clothing, and scars. Photos or renderings can also be uploaded.

All of the information is made available online to anyone looking for a missing loved one.

"We've had five successful ID's where people originally saw something on NamUs, which sparked them to make calls and ask ‘Hey, I'm missing this person or that person," explained William Pellan, director of investigations for the District Six Medical Examiner, which covers Pinellas and Pasco counties. "I think someone you have there might be a brother, uncle or mother and can you look into it further,’”

One such case was a man found dead in Clearwater. He didn't have an ID on him and his fingerprints didn't come back with a match. The medical examiners office put his information into NamUs along with a sketch of his face.

About a year later, they got a break when a woman in New York saw a public service announcement for NamUs and went to the database.

"She saw that PSA and started searching," Pellan said. "She knew her brother was last known in Florida or the Tampa area. That picture came up and she knew right away that was her brother."

It was one of the first successful identification matches from NamUs in Pinellas County, which was confirmed through a DNA sample.

Investigators hope more families and friends with missing loved ones will utilize the database.

"It gives them hope," Pellan said. "A place to go and get involved and do something to try and find their loved one."

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