More than 20 years have gone by since William Walter Brooks Jr. went missing days after his 17th birthday.

The Frederick teenager was last seen leaving his father's home on Aug. 25, 1992.

He was on probation for a juvenile offense and was supposed to meet up with his probation officer later that day, but he never arrived at the appointment, Frederick police Detective Gene Alston said.

Over the years, police followed many leads that didn't pan out. Alston said he believes foul play was involved in William's disappearance, but there is no proof.

"There was no reason for him to just disappear on his own," Alston said.

William would be 37 if he is still alive. At the time he went missing, he was described as a black male, about 6 feet tall and 150 pounds, with brown hair and brown eyes. He had a pierced left ear and was nicknamed "BB."

"It is our hope to find William Walter Brooks Jr. alive and well, or at least be able to return his remains to his family for closure," Alston said. "If there is foul play involved with William Walter Brooks' disappearance, the Frederick Police Department would like the opportunity to arrest the individual[s] responsible."

Anyone with information can call Frederick police at 301-694-2100 or the National Center for Missing and Exploited Children at 800-THE-LOST (843-5678).