LYNN – It has become a poignant ritual for police detectives who spoke briefly with Juan de la Cruz Monday and assured the Florida resident that the search for his missing son has not slipped off their investigatory radar.De la Cruz checks in with police once or twice a year, often on the Sept. 28 anniv-ersary of his son’s 1996 disappearance or on his Jan. 3 birthday, to see if police have anything new to say about the investigation. Detectives don’t have much to tell him but they make sure they have a way to contact him if and when they do.”It’s still one of our top priorities,” said Acting Chief Kevin Coppinger referring to the 13-year-old search for Jesus de la Cruz.The 6-year-old boy was last seen on a sunny Saturday afternoon by other children who saw him standing with a man and a dog on the corner of Park and North Common streets. Police worked around the clock to find the boy.They searched his 22 Park St. home and the Commons neighborhood for clues to what happened to him. They stopped motorists a week after the disappearance and asked them if they had seen the boy. An FBI agent spent the next year working with Lynn police on the case.They arrested Robert Levesque, the man seen with de la Cruz, a day after the disappearance on charges unrelated to the missing boy and questioned him. Local newspaper reports said police wanted to learn more about information suggesting the boy was interested in a child’s bicycle Levesque showed him.Levesque was released from police custody shortly before Thanksgiving 1996.Over the last decade, interest in the boy’s disappearance has dwindled down to a small group that includes Juan de la Cruz, the boy’s mother, Magdalena, and the National Center for Missing and Exploited Children.The Center’s site features details of de la Cruz’ disappearance and a computer-enhanced photograph depicting him as a 19-year-old. Like retired Capt. Joseph Rowe before them, detectives track down all leads and tips concerning the boy. Two recent ones proved unfruitful.”It’s frustrating. Frankly, you would think we would know something for better or worse by now,” Coppinger said.De la Cruz is one of two Lynn boys listed on the Center’s Web site. Giovanni Gonzalez was added last year after he was last seen at his father’s downtown apartment. His father, Ernesto, remains jailed on charges, including lying to police, but he has not been charged in connection with his son’s disappearance despite a November 2008 murder confession.