A couple and their 16-year-old son have died while trying to save the family dog during a walk along a California beach.
Howard Kuljian, 54, was playing fetch with pet dog Fran at Big Lagoon beach, near Arcata - around 280 miles north of San Francisco - as a 10-foot surf churned the water just feet away.
Signs near the beach did warn of 'sneaker waves', the kind that suddenly roar ashore without much warning, according to csmonitor.com.
Kuljian had thrown a stick for his dog, which landed near the water's edge. The animal chased after it and, before they knew it, was swallowed by the huge wave.
His son, Gregory, 16, ran to save the dog but was captured by the surf himself. Kuljian ran in to help his son, who managed to pull himself back onto the sand.
But, realising his father was drowning, Gregory, along with his mother, went in to save him.
The couple's 18-year-old daughter, Olivia, and Gregory's girlfriend could only watch as the tragedy unfolded.
A bystander called police, but by the time help arrived it was too late.
The Coast Guard deployed a helicopter and two motorised lifeboats to try and find Gregory, but thick coastal fog rendered the search impossible.
Deputy Roy Reynolds from the Humboldt County Sheriff's Dept, told AP: "Arcata Fire Department and State National Parks, they arrived on scene and had trouble accessing the area, because the sand is really soft up here. They got up to the area of the incident and recovered one person fairly fast; the second person was washed ashore and recovered; the third person is still missing."
Signs posted near the parking lot at Big Lagoon beach warned beachgoers not to turn their back to the surf and to pay special attention to sneaker waves.
Coast Guard Lt. Bernie Garrigan told csmonitor.com: "Because the beach is designed that way, when that 10-foot wall breaks, it surges up on the beach and surges back really fast. It's like a cyclical washing machine."
A state parks district superintendent, Dana Jones, added: "When there is shorebreak like that, you don't even have to go into the water to be pulled into the sea. It's a reminder to be real careful around the ocean."
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