DEL NORTE, Colo. -- Human remains retrieved from a barrel in an Arizona lake are that of a Colorado mother who disappeared from Monte Vista more than seven years ago.

Officials in Rio Grande County held a news conference Tuesday to announced that DNA tests confirmed the remains were that of Danice Day. The test results came back on Sept. 18, after analysis at the El Paso County Coroner's Office.

Day was 19 when she disappeared from Monte Vista in 2002. Her boyfriend, Victor Braun, said she was going out with friends and she never came back. Investigators said she left her car and cell phone at the home the two shared.

The remains were found in a barrel in Arizona's Lyman Lake, near St. Johns, in June after Colorado authorities were directed there.

Sheriff Brian Norton said that investigators were able to locate Day's remains through "negotiations" between Braun's attorney and prosecutors.

Rio Grande County District Attorney David Mahonee said Braun, 33, has been charged with manslaughter.

District Attorney Mahonee said that Braun would be pleading guilty to manslaughter. He is due in court on Nov. 3.

"It wasn't really a plea bargain. It was negotiation on a contract. We are not at liberty to discuss any plea bargain at this point," Mahonee said during a news conference.

Norton said the investigation is continuing and if other people assisted in disposing of Day's body they will be charged.

"The investigation continues into that person, or those persons, that had knowledge or assisted in the disappearance of Danice Day," he said.

Braun is the father of one of Day's two children.