EDINBURG – A Mission man facing disturbing charges nearly two decades after his alleged crimes appeared in court Wednesday. He’s the main focus of an investigation into child sexual assault.

One of his alleged victims tipped off police.

Authorities say some of the victims could be 17 to 18 years old now. They’re asking for potential victims to come forward.

Luis Nava, Jr., 53, plead not guilty to the 18 counts against him.

“He's facing three counts of aggravated sexual assault with a child, he's also facing seven counts of sexual assault with a child and eight counts of indecency with a child sexual assault,” said Sgt. Maria Montalvo, spokeswoman for the Department of Public Safety.

DPS and Texas Rangers are asking for other alleged victims to call 956-565-7600.

Watch the video above for further details.