LONG VALLEY, N.J. (AP) _ A fire destroyed a wooden barn at a boarding stable Monday, killing a young couple, their infant son and 16 horses, and injuring two people.

Dale Bowlby, 22, and his wife, Sherri, 20, and their 7-month-old son Robert were in an apartment above the barn at the Snowbird Acres Farm when the fire erupted shortly before 5:40 a.m., said Sgt. Jack Dempsey, a spokesman for the Morris County prosecutor's office.

The blaze was brought under control within two hours, but its cause and origin were under investigation, said Dempsey.

Farm owner Martin Siegel said he was awakened by stablehand Norman Ayers, 34, who jumped out of a second-story barn window and raced to the main building, about 100 feet away, after smelling smoke.

Ayres was admitted to Hackettstown Hospital and treated for smoke inhalation.

''Words can't really describe it,'' Siegel said of the fire. ''There were no sounds, it was quiet.''

Mrs. Siegel said she and her husband tried to enter through the back of the barn to search for survivors.

''It was too hot,'' she said. ''There was just no point. And the horses weren't making any noise. I had a feeling they were probably dead already.''

She added that there seemed ''no point in risking any lives, going after horses that were already unconscious.''

''I can't tell you the story of each horse and what they mean to me,'' she said.

The Bowlby family had arrived at the farm two months ago in response to an employment ad, Siegel said.

''She took care of the baby, he took care of the grooming,'' said Siegel.

A police officer was treated at Hackettstown Hospital for minor injuries and released.

The apartment was was equipped with smoke detectors, Mrs. Siegel said.