This week marked one year since Texas teen Caleb Diehl disappeared, but what happened to him remains a mystery.
Caleb left his mother's home in Nocona, Texas on March 30, 2015 to head to a part-time job working for a family friend. Because his personal vehicle was in the shop, Caleb was driving a pick-up truck belonging to that friend, Ricky Dale Howard.
Several days later, the pickup mysteriously reappeared at the business, and the keys to it were on their proper hook at the business.
But there was no sign of Caleb.
"We are no closer to knowing what happened than we were months ago," Tami Diehl, Caleb's mother, recently told Dateline. "I'm at a loss to know what to do. I just know that I can never give up searching for answers."
Nocona Police Department Chief Kent Holcomb told Dateline there has not been a break in the case, and they are still asking anyone with information to come forward. “It’s a very unfortunate situation. We’re following up on anything that we get, but there just haven’t been any answers,” Chief Holcomb said.
There is one person from whom police say they have an interest in learning more; Ricky Dale Howard, the man Caleb borrowed the pick-up from and who, possibly, was the last person to see Caleb before he disappeared. Chief Holcomb told Dateline thatHoward has not been cleared in the case, but stressed he is only one of several peoplethey have questioned in relation to the case.
Howard, who had been a family friend for years, was arrested on an unrelated weapons charge in May 2015. Officials had found several firearms when he gave them permission to search his properties after Caleb vanished.
More recently, in December 2015, Howard was charged with two counts of aggravated sexual assault of a child. In January, two more counts were filed after authorities in Montague County say a second victim came forward. Howard is currently out on bond.
No trial date is set on the sexual assault charges, but a trial on the gun charges could come as soon as June.
Related: Days After Caleb Diehl Vanishes, Truck He Was Driving Reappears
The Diehl family continues to have their suspicions as to what may have transpired a year ago, and are hoping someone will soon provide the information needed in order to bring Caleb home, one way or another. Family and friends held a candle-light vigil Wednesday to mark the one year anniversary of Caleb’s disappearance.
"I've gone over the timeline so many times. We've talked about it so many times as a family, and we are all on the same page," Caleb's mother Tami told Dateline. "But there has to be proof, and anybody who knows something needs to tell us. Please."
Caleb Diehl is described as 6'2" tall, weighing 145 lbs., with blond hair and blue eyes. If you have any information about his whereabouts, please contact the Nocona Police Department at (940) 825-3281. You can also visit the Facebook Page 'Bring Caleb Diehl Home' for more information.