Monterey Park, California (CNN) -- Actor Robert Wagner isn't a suspect in the reopened investigation into the 1981 drowning death of his wife, actress Natalie Wood, but authorities have received "substantial" new information to initiate a new inquiry, Los Angeles County authorities said Friday.
"We have several sources coming forward with additional information and we have found it credible enough to take another look at the case," Los Angeles County Sheriff's Lt. John Corina said outside the sheriff's headquarters in Monterey Park, California.
"This new information is substantial enough to make us want to take a new look at the case," he added.
Corina declined to comment directly on new statements made by the captain of the yacht on which Wagner, Wood and actor Christopher Walken were passengers off Catalina Island near Los Angeles at the time of Wood's death.
The yacht captain, Dennis Davern, offered a new account Friday about how Wood's death was reported and said Wagner waited hours to call the Coast Guard after Wood went missing.
When asked if the captain could face charges for possibly lying to authorities during the 1981 investigation, Corina responded: "That, I can't say. We'll probably end up talking to the captain sooner or later, and we'll assess what he has to say then and now."
When asked whether authorities will question Walken, Corina declined to say whom two investigators will be interviewing.
"I'm not going to comment on who's going to be talked to or who's not going to be talked to. I think you can speculate on that," Corina said.
The approaching 30th anniversary of Wood's November 29, 1981, death isn't playing a factor in the new inquiry, he said.
"We're not concerned with the anniversary date," Corina said.
"We're going to follow up on leads we have," Corina said. "We're going to interview some people. We're going to interview some new people."
Wood's death is still ruled an accident, he said.
"Her death is ruled an accidental drowning. ... Until we find something that says it isn't, until that time, it's still an accidental drowning," Corina said.
Earlier Friday, Davern said Wagner told those aboard the boat what to say to authorities about the incident. Wood was later found drowned.
Davern said he first searched the boat to check whether Wood was anywhere on board. He said he then wanted to turn on the searchlight to see whether she was in the water, but Wagner told him not to.
"We don't want to do that right now," Davern quoted Wagner as saying.
After four hours, Davern called the Coast Guard. He now says he regrets waiting so long.
"It was like a mistake that I made. I do regret that, yes. I do, really," Davern said Friday.
"We didn't necessarily really lie. We just didn't tell everything, and it was agreed that what we spoke about between the three of us is what we're going to tell the investigators," Davern said.
Last year, Lana Wood, the actress' sister, and Davern asked the sheriff's office to reopen the case. L.A. County Sheriff's Deputy Benjamin Grubb couldn't say whether the sister and the captain prompted the renewed investigation.
"This is about Natalie and for Natalie," Lana Wood told CNN's Piers Morgan on Friday night. "It is not for anyone else. It is time that Natalie's actual voice was heard. That's what I am hoping will come from the investigation."
She said it was time for all of the circumstances of the death to come out.
"Only RJ (Wagner) and Natalie know. And only one of them can speak," Lana Wood said. "It's time for the family to hear the truth, that's all."
Despite authorities' assertion that publicity surrounding the 30th anniversary of Wood's death isn't a factor in reopening the case, one legal analyst who's a former federal prosecutor believes otherwise, saying media accounts are playing a role.
"The fact that it's the 30th anniversary makes more people interested in it again, including the investigators who might be interested in opening it again and maybe willing to put extra time in and make a finding on what actually happened," said Annemarie McAvoy, a Fordham University School of Law adjunct professor and a former assistant U.S. attorney in New York.
But McAvoy said it's "probably very unlikely" any criminal charges will be filed. "They are going to have to show a motive for murder."
"It's a true Hollywood mystery," she added. "It's like a movie you would see, except it's real life. I think it's one of those things that will stay a mystery."
Authorities announced Thursday the reopening of the investigation into Wood's death, which happened after an argument as the couple was boating off Catalina Island.
Wagner's publicist Alan Nierob issued a statement Thursday saying the actor's family "fully support the efforts of the L.A. County Sheriff's Department and trust they will evaluate whether any new information relating to the death of Natalie Wood Wagner is valid, and that it comes from a credible source or sources other than those simply trying to profit from the 30-year anniversary of her tragic death."
Nierob said no one from the sheriff's department has contacted Wagner or anyone in his family about the case, one of Hollywood's most enduring mysteries.
Natalie Wood once said in a televised interview that her greatest fear was of dark seawater. Davern said that's why he felt it was doubtful Wood had taken the yacht's dinghy to try to go ashore.
Wood's body was found floating in the water about a mile away from the yacht.
According to police reports, Wood was found wearing a long nightgown, socks and a down jacket.
"My sister was not a swimmer and did not know how to swim, and she would never go to another boat or to shore dressed in a nightgown and socks," Lana Wood said previously.
The autopsy report shows that Wood had two dozen bruises on her body, including an abrasion on her left cheek and bruises on her arms. Davern said he saw no bruises when the actress was aboard.
Although the county coroner's office ruled that Wood's death was an accident, others say the case hasn't made sense.
In 2010, Lana Wood said that she believes a highly charged argument between her sister and husband on the yacht's back deck preceded Wood's drowning. She said she does not suspect foul play.
"I can't imagine that he (Wagner) purposely would have done anything to hurt Natalie," Lana Wood told Morgan on Friday. "However, I know things happen when there is too much drinking and fighting."
Davern broke his long silence with a detailed account in "Goodbye Natalie, Goodbye Splendour," a book he wrote with his friend Marti Rulli. It was published in September 2009.
He said Friday that he is not trying to profit from the anniversary and that he has no reason to lie.
Davern has said he believes Wood's death was a direct result of the fight with Wagner.
Wood and Wagner married in 1957, divorced in 1962 and remarried in 1972. They often sailed their yacht off the coast of California and they had invited Wood's "Brainstorm" co-star, Walken, to join them on a sail on Thanksgiving weekend in 1981.
Walken and Wood had been filming "Brainstorm" at the time and the Hollywood rumor mill was abuzz with speculation that Wagner was jealous over Walken, but authorities have said Walken witnessed only the events leading up to an argument between the couple.
Walken couldn't be reached immediately for comment.
Wagner admitted his jealousy in his book "Pieces of My Heart," also published in September 2009. He acknowledged that there had been a fight with Wood, writing that he smashed a wine bottle on a table.
After Wagner argued with Walken and broke the wine bottle, Wood left in disgust and went to her stateroom, Davern said. Walken also retired to a guest room, Davern added, and Wagner followed his wife to their room. A few minutes later, Davern said, he could hear the couple fighting.
Embarrassed, Davern said, he turned up the volume on his stereo. At one point, Davern recalled, he glanced out of the pilot house window and saw both Wagner and Wood on the yacht's aft deck. "They'd moved their fight outside. ... You could tell from their animated gestures they were still arguing," he said.
A short time later, Wagner, appearing to be distraught, told Davern he couldn't find Wood. After failing to find Wood aboard and noticing the dinghy gone, Wagner shrugged and poured them both drinks, Davern said. He suggested his wife had probably gone off in a temper.
Wagner's story, as told in his book, differs from Davern's. He maintains that after the argument with Walken, Wood went to her room and prepared for bed while he and Walken sat on the deck, cooling off.
Wagner writes that he went to check on Wood, but she wasn't there. Wagner wrote that he assumed his wife had gone ashore on her own.
He radioed the restaurant on shore where they'd had dinner and called the harbor master to see if anyone had seen Wood.
The dinghy was found about a mile from the yacht and a mile from where Wood's body was found.
"I don't think she fell," Lana Wood said Friday of her sister. "I don't know if she was pushed. I don't know whether there was (an) altercation and it happened accidentally. She shouldn't have died."
Wood's first starring role was as a child in "Miracle on 34th Street" in 1947, and she played alongside some of Hollywood's top leading men: James Dean in "Rebel Without a Cause" and Warren Beatty in "Splendor in the Grass." She was nominated for Oscars in both of those films, as well as for "Love With the Proper Stranger" (1963), according to the IMDb website. One of her more memorable roles was as Maria in "West Side Story."
Wagner's striking good looks landed him roles in dozens of films in the 1950s and '60s before he hit it big in television. He starred in two popular series, "It Takes a Thief" (1968-70) and "Hart to Hart" (1979-84), and more recently as Number Two in the "Austin Powers" spy spoofs.