John Gerrish, Ellen Chung and daughter Muji.Photo: Rosanna Heaslett

As the investigation into themysterious deathsof a family of three and their dog continues, a portion of a river located near to where they were found in a remote area of the Sierra National Forest has been closed due totoxic algae.
“These algal blooms can produce toxins thatcan make people and pets extremely sick,” Elizabeth Meyer-Shields, a Bureau of Land Management field manager, said in a statement. “We will continue to monitor for the algae’s presence and look forward to when the public can safely recreate in the Merced River.”
The news was shared days after officials with the Sierra National Forest announced that several trails and campgrounds around the Merced River Recreation Site were closed “due to unknown hazards.”
The closures came two weeks after John Gerrish and Ellen Chung were found dead alongside their 1-year-old daughter, Miju, and the family dog, Oski, in the Devil’s Gulch section of the Hites Cove Trail on Aug. 17.
John Gerrish, Ellen Chung.Courtesy Steven Jeffe

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Aninitial autopsyyielded little information about how the family died, although authorities have been able torule out two causes of death: exposure to chemicals along the trail and use of a gun or another deadly weapon.
“We know the family and friends of John and Ellen are desperate for answers, our team of detectives are working round the clock,” Sheriff Jeremy Briese said in a previous statement to PEOPLE.
RELATED VIDEO: Family and Dog Mysteriously All Found Dead, Prompting Officials to Declare a ‘Hazmat Situation’
“As of the date of this update cause of death remains a question,” the sheriff’s office said. “Detectives continue conducting interviews and investigating all potential possible explanations.”
source: people.com