LAWRENCE, Kan. (AP) — Two northeast Kansas parents are increasingly frustrated with the investigation into their son’s disappearance 26 years ago.

The Lawrence Journal-World reports that Randy Leach was a teenager when he mysteriously disappeared in 1988 from a graduation party. He would now be 44.

Earlier this year, his parents, Harold and Alberta Leach, learned that law enforcement, including the KBI and the FBI, had had a suspect in the 1990s. That suspect, Eric Montgomery, died in prison four years ago.

Montgomery also had been a suspect in two 1990 homicides that occurred seven miles from the Leaches’ home in rural Linwood.

Harold Leach, now 73, said he was saddened when he found out law enforcement had withheld information from him and his wife.