TULSA, Oklahoma - The Tulsa County District Attorney has filed murder charges against three people in the disappearance of Courtney Palmer. Police believe Courtney Palmer witnessed a shooting back in November - and he hasn't been seen since.

Originally facing assault with intent to kill and kidnapping charges - Gerald Lowe, Michaela Riddle and Jeannetta Thomas are now charged with murder.

Investigators say they found human remains in Muskogee over the weekend, and believe they could be Palmer's. They still have to positively ID the remains.

There are currently 78 reported homicides for the city of Tulsa this year. In 6 of them - police still haven't made any arrests.

If you have any information about Palmer's disappearance or any of Tulsa's 78 homicides, call Crime Stoppers at 918-596-COPS.