Updated

Investigators in Missouri are searching for more human remains in an area where law enforcement has already found two human skulls.

More than 100 investigators were on the scene Thursday near Belton, 20 miles south of Kansas City, looking for clues to help identify the second set of remains.

One of the two sets of remains was identified Wednesday as 21-year-old Jessica Runions, who disappeared from a party in South Kansas City last September. Her case is now being investigated as a homicide.

The second set of remains has not been identified, but investigators believe they may belong to Kara Kopetsky, a 17-year-old who disappeared in May 2007. She was last seen leaving Belton High School.

Rhonda Beckford, Kara's mom, was with the Runions family when word broke of the identification. Beckford says she believes the second set belongs to Kara but was told it could take up to a year to make a positive identification.

"I don't know what to think," Kara's mother, Rhonda Beckford, told Fox 4 KC. "I'm hopeful that it doesn't take that long. But we've waited 10 years. The only thing I can say is we're almost there."

Kylr Yust, a friend of Jessica Runions' boyfriend, has been charged with burning Runions' car, which was found two days after he disapparance. His trial on that charge is set for October. He has not faced additional charges in relation to Runions' disappearance.

Yust, 27, was also involved with Kara Koptesky before her disappearance. Kara and her mother filed a restraining order against Yust shortly before she vanished. The order wasn’t officially granted until after she disappeared.

In 2011, Yust was charged with two counts of animal abuse and was placed on two years probation after pleading guilty to choking and beating his 18-year-old pregnant girlfriend.

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