US police want to reinterview Robert Wagner, the 87-year-old widower of Natalie Wood, as new details emerge that could lead authorities to solve the mystery of the US actress’s death nearly four decades later.

Wood, who starred in West Side Story and was nominated for three Academy Awards, was found dead in the waters off Southern California’s Catalina Island in 1981. Investigators initially ruled the death accidental. But the case was reopened in 2011 after the captain said he heard the couple arguing the night of her disappearance.

Wood’s death has been classified as suspicious and Wagner has been named a person of interest in the case, officials said.

Detectives haven’t reached out to the US actor for more than five years, Wagner’s publicist and a sheriff’s spokeswoman said.

Wagner, who is known for his roles in the 1980s TV series Hart to Hart and the Austin Powers movie franchise, has denied any involvement in Wood’s death. His lawyer has said he fully co-operated with investigators.

Several new witnesses have come forward since the case was reopened, including one who described hearing yelling and crashing sounds coming from the couple’s stateroom, sheriff’s Lieutenant John Corina said.

Shortly after that, separate witnesses who were on a boat that was in the water nearby, heard a man and woman arguing on the back of the boat and believe the voices were those of Wood and Wagner, Corina said.

Wagner’s statements to investigators after Wood’s death and subsequent comments about the case “really don’t add up to what we found,” the lieutenant said.