A second murder charge has been filed against a Washington state man accused in the death of a Canadian couple 31 years ago.

William Earl Talbott is facing two charges of aggravated first-degree murder, according to court documents filed Friday in Washington state's Snohomish court.

The bodies of Victoria's Tanya Van Cuylenborg, 18, and her high school sweetheart Jay Cook, 20, were found in 1987 about one hour's drive apart in Washington state.

Jay Cook's body was found wrapped in a blue blanket under this bridge in Monroe, Wash., 11 kilometres from Talbott's parents' home. He had been beaten and strangled. (CBC archives)

The Skagit County Sheriff's department announced Talbott's arrest last month after investigators made a break in the cold case using a new strategy involving genetic genealogy, uploading DNA from the crime scene to a public, online genealogy database.

Investigators then combed the family tree to identify Talbott as a suspect and collected a fresh DNA sample from him to confirm a match.

Talbott, 55, was arrested in May and charged with the first count of first-degree murder in Van Cuylenborg's death, with investigators saying at the time that they expected to lay a second charge in Cook's death after gathering more evidence.