(LOS ANGELES) -- The husband of a California woman who is believed to have vanished while diving off the Los Angeles coast is now being questioned by homicide detectives, after investigators searched for her body for four days and failed to find it.
Rebecca Weiss, 50, was free diving in a cove near Rancho Palos Verdes on Saturday, her husband, Alan Weiss, told police. Rebecca, an experienced diver, had gone diving alone, they say he told them.
When she didn't return, Alan, 60, said he went to search for her in areas where the two would frequently dive. He told authorities that he found his wife's car in a parking lot and her dive bag on the shore where she presumably entered the water.
For four days the Coast Guard sent up a helicopter to look for her, while divers and life guards were sent to search for Rebecca.
Rebecca's mother, Vilma Causey, told ABC News Thursday that her daughter is an experienced diver who was swimming in calm waters near a popular beach.
"I was there yesterday because I wanted to see where this happened, and it's in a cove, it's nice water. There's no strong waves or anything like that. It is a very, very busy place, a big hotel and restaurant. It's for tourists and everybody. There are a lot of people. If she was there, somebody would see her," Causey said.
Causey declined to speculate about whether something suspicious happened to her daughter, saying that she would wait for the investigation to be completed. She said that Rebecca and Alan have been together for 25 years, married for more than 18, and that they seemed to be happy.
"I get along with him. They seem to be happy, they were nice to each other," she said. "Maybe they have their own thing, like any married couple. I'm not so involved in that."
Rebecca Weiss, who works as a bookkeeper for one of her husband's business partners, is an avid traveler who spent time in India volunteering at an orphanage, Causey said. Her dream was to open an orphanage in Costa Rica.
Causey, 72, said that her daughter's bag was found at the bottom of the steps leading down a hill to the beach.
"She is a very good diver, a very good swimmer, very healthy to be able to do all this. She has been diving all over different places," Cuasey said. "I just want to find out, bad or good. As a mother I will always say, 'No, she's okay,' but if it doesn't come out like that, at least we'll find out."
Los Angeles County sheriff's homicide detectives are now interviewing Alan Weiss, according to ABC station KABC-TV.
According to Alan Weiss, the last time he saw her was when she drove away from their home in Marina del Rey, Calif., wearing her wetsuit, The Los Angeles Times reported. On Saturday she drove 23 miles south to Rancho Palos Verdes to dive at one of the couple's favorite diving spots.
Lt. Holly Francisco of the Los Angeles County Sheriff's Homicide Bureau said that Alan Weiss has fully assisted police.
"He's been cooperative with our investigators, as well as the other members of the family," she said. "He was the last person to see her, so he is being interviewed, but he is being cooperative."
Investigators are not certain if Rebecca met anyone on her way to the Rancho Palos Verdes.
Free diving is a form of underwater diving that involves no scuba gear, with divers relying solely on their ability to hold their breath for long periods of time before resurfacing. Though most free divers, like Rebecca Weiss, are experienced swimmers, there inherent risks.
One of them is known as a shallow water blackout, in which a diver loses consciousness at the end of a dive, typically within 15 feet of the surface. Free divers frequently push themselves to their physical limits, and often use weights during their dives.
Rebecca Weiss was described as Asian, 5 feet 5 inches tall, about 115 pounds, with black hair and brown eyes. Anyone with information was asked to contact the Los Angeles County Sheriff's Department at (323) 890-5500.
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