GRAND PRAIRIE, Texas (AP) _ An idle, dormitory bull session apparently led to the arrest of a Naval Academy midshipman and her boyfriend, an Air Force Academy cadet, in the December slaying of a 16-year-old girl.

According to unidentified Navy sources cited in Friday's editions of The (Baltimore) Sun, two first-year female midshipmen apparently were relaxing off-duty, when the conversation turned to the question: ``What's the worst thing you have ever done in your life?''

The answer of plebe Diane Zamora, 18, was simply murder.

Zamora's roommate told academy officials and police interviewed the midshipman at the academy in Annapolis, Md., last week, the Sun said.

Zamora was arrested Friday at her Fort Worth home and charged with the murder of Adrianne Jones, who was found shot to death Dec. 4 on a farm road in Grand Prairie, between Dallas and Fort Worth.

Police said her cadet boyfriend, 18-year-old David Graham of Mansfield, awaiting extradition in Colorado, gave a written statement earlier this week that he had killed his ex-girlfriend and his current girlfriend, Zamora, was an accomplice.

``Both of them played a significant role in the death of Adrianne Jones,'' said Deputy Police Chief Brad Geary, but did not elaborate.

Ms. Jones, a popular honor student and athlete who lived in Mansfield, a small town south of Fort Worth, had been had been shot twice in the head. ``Jealousy and anger'' were motives for her death, police said.

Zamora, on leave from the academy since last week, was held on $250,000 bond.

Officials at the military academies said they are cooperating with law enforcement officials and referred questions to police.

The arrests were not the first in the slaying. A 17-year-old boy, described as a high school dropout, spent nearly a month in jail charged with the murder, but the charges were dropped and he was released in January.