David Packett, the 26-year-old advertising manager of a Virginia weekly newspaper, was working late Wednesday when he received a cryptic telephone call warning him of a "mummified" body hidden in a Fredericksburg Funeral home.

"It was like something out of Starsky and Hutch," Packett said in an interview yesterday. "The caller claimed to know that I could find the remains of an infant there. I was flabbergasted. Then the caller volunteered to meet me with pictures of the body."

Packett's disbelief dissipated the following day when his caller arrived at the newspaper with pictures "of a body in infant's clothing in a cloth covered, wooden casket, with the dusty remains of flowers draped about it."

Packett left his office in Montross, a town about 60 miles south of Washington, and headed for the Wheeler and Thompson Funeral Home in Fredericksburg. There Packett said he was brusquely denied access to the vaults by employes who told him his story was "absolutely ridiculous."

Undaunted, Packett took the pictures to Sgt. John R. Lightner of the Fredericksburg City police who was allowed to enter the vaults Friday evening. "Sure enough, we found the body in a receiving vault behind draperies in the chapel of the home," the officer said. The body "looked at least 20 years old. We can't even tell you what sex it is."

The infant's body was taken to Richmond where medical examiners are attempting to determine "the age and posible identity of the baby, and how it may have died."

The discovery has caused something of a sensation in Fredericksburg, a city of 16,000. "I've lived in this city for 36 years and can't remember anything like it," Lightner said. "It's a little spooky."

Both Packett and Lightner acknowledged that "there had been rumors" circulating about the body in the community a few days before the telephone call. Packett, who works at the Westmoreland News, has declined to name the person who called him.

Wheeler T. Thompson, whose family has run the Fredericksburg funeral home for the last 140 years, said yesterday he may have a solution although he conceded that "no one was more mystified than I was" to see the body.

"I knew that those vaults haven't been opened in 20 years," the 74-year-old Thompson said.He said he could vaguely recall a woman telling of his father's taking the body of a child "well before the flood of '42" and placing it in the vaults.

"Well, the weather was real bad and wet then," Thompson continued, "and my father told the couple that he would take the body back until they claimed it . . . As far as we know, they never came back.

"That may not be the answer, but it's the best lead I've got," Thompson said.

Thompson was also miffed at Packett and the police for pursuing an investigation. "I think it's all uncalled for," he said.