ALFRED — A young New Hampshire man murdered last summer may have been blackmailing the man accused of killing him, according to a police affidavit.

The body of Aaron White, 23, of Exeter, N.H., was found in July at a weigh station in Kittery.

Jeffrey Sibley, 41, of Chesterfield, N.H., is charged with fatally shooting White, a clerk at a convenience store, on July 16. Sibley pleaded innocent at his arraignment in York County Superior Court Tuesday.

White began blackmailing Sibley after Sibley had paid him for sex, according to Patricia Sloan, who co-owns a plumbing business with Sibley’s brother, Allen.

Jeffrey Sibley told his brother in June that White was trying to extort $2,000 from him and that he was “going to take care of it,” Allen Sibley told police, according to the affidavit.

Prosecutors allege Sibley settled the matter with two shots fired from a .45-caliber handgun, a Glock Model 21 his brother bought in Bellows Falls, Vt.

White was last seen around 10:22 p.m. July 16 at the Exeter service station where he worked. A customer found the station open but unstaffed and called police.

White’s body was found six days later. The investigation quickly centered on Sibley, according to the affidavit.

White’s girlfriend, Heather Gigliotti, told police Sibley had called looking for White the day he disappeared. Sibley had known White for about five years and was considered a good friend, she said.

Questioned on July 29, Sibley told police he had been home drunk in the early morning hours of July 17, when the murder is believed to have occurred. His statement was corroborated by Patricia Sloan’s son, Leland, according to Detective Sgt. Michael Sperry of the Maine State Police.

On Aug. 14, police say Patricia Sloan told them that Sibley had called her on July 17 and admitted killing White. Sibley pressured her son to support Sibley’s alibi, Sloan said. She said Sibley had been paying her son, as well as White, for homosexual acts.

“According to Patricia, Leland went along with the alibi out of loyalty,” the affidavit states.

Sibley fled after being questioned by police. He was arrested last week at a motel in Valley City, N.D., after the case appeared on the television show “America’s Most Wanted.”

Gigliotti and Joan Wilson, White’s mother, attended the arraignment.

“Good job!” Wilson yelled as Sibley was escorted out of the court. “I hope I can do the same for you someday.”