They found the mystery boy, crying and confused, before dawn Saturday in the cluttered old bus terminal here. He had no money, no identification; he indicated that he could neither talk nor hear.

During the next few days, police and social workers in this high-plains capital "moved heaven and earth," as one detective put it, to learn anything about the shy, skinny young man who seemed to have no past.

Then the media stepped in.

On Monday, newspapers around the country printed photos of Cheyenne's "mystery boy," as he came to be called. Early this morning, the telephones started ringing at police headquarters, and tonight the mystery seemed solved.

Reacting to the newspaper photos and police descriptions, callers told detectives here that the stranger appeared to be Gordon Vanderberg, who has been treated for hearing impairment and mental difficulties in Los Angeles and in New York state.

Tonight, Police Lt. James Barker confirmed the youth's identity, and said Vanderberg has a criminal record in New York and New Jersey.

Barker said Vanderberg, 22, identified himself to officers as "Bruno Acerro," but his fingerprints matched those on file in New Jersey as belonging to Vanderberg.

"We know at this point that he has been charged and has some convictions in . . . New York and New Jersey -- more than one violent felony," Barker said.

He added that the record lists "such things as robbery and arson" and that the charges were recent.

"I feel like a real idiot," Ellen McGee said tonight. McGee, a foster mother, had taken Vanderberg into her home and vehemently defended him.

"Basically, the media solved this mystery," police detective Marty Luna said earlier. "They did a fantastic job of blitzing his picture all over the U.S. . . . . It's like the whole country was one small town. When they get the word out, you're going to find somebody who can solve these puzzles."

A custodian at the Trailways terminal first found the youth about 4 a.m. Saturday, carrying a letter evidently written to him and signed "Mommy."

"There's a lot the world can offer you that I can't," the handwritten letter said. "I hope you will find someone to teach you the basic[s] such as reading and writing."

The mysterious stranger and his mysterious letter quickly captured the attention of this friendly city. The McGee family took him in, and special-education professionals tried to converse with him through drawings and sign language in an effort to derive some clues about his identity.

"It's very difficult to communicate with him," said Ralph McConahy, a social worker who spent hours trying to elicit information from the youth. "He gives you motions and tries to demonstrate as best he can."

Although the experts were convinced that the youth was illiterate, deaf and mute, Barker said tonight that Vanderberg can read and write. And the driver of the bus on which the youth rode into Cheyenne said the young man had talked to him during the trip from Denver.

While there were still some questions tonight about Vanderberg and why he came to Cheyenne, one thing was clear: he was spending the night in the Laramie County Jail.