An explosion leveled a house near Fort Pierre, South Dakota, Wednesday, killing two grandparents and their 6-month-old granddaughter.
Reached by phone Thursday, Stanley County Sheriff Brad Rathbun confirmed to Fox News Digital that Ladonna Hupp, 61, and 6-month-old Harper Hupp were found dead at the scene.
William "Bill" Hupp, 66, was rushed to Avera St. Mary's Hospital in Pierre, where he later died of his injuries. Two boys were also rushed to the hospital and have since been airlifted to a burn center in Minnesota, Rathburn said, adding that the cause of the explosion remained under investigation.
Rathbun also told Fox News Digital that foul play was not immediately suspected, and the South Dakota State Fire Marshal's Office was handling the probe into the cause of the blast.
A neighbor reported hearing a loud explosion around 10:20 a.m. Wednesday and alerted authorities, according to KELO-TV. The blast sent debris flying 50-100 yards in all directions, flattening the home. Only some playground equipment remained standing as of Wednesday afternoon, the outlet reported.
Fox News Digital also reached out to the South Dakota State Fire Marshal's Office Thursday seeking more information but did not immediately hear back.
Reached by phone Thursday, Fort Pierre Mayor Gloria Hanson noted the explosion happened outside city limits but offered sympathies to the family.
"The investigation is still ongoing and there is a lot of privacy involved for the family and I just hesitate to make any public comments at this time," Hanson told Fox News Digital. "It's a small, close-knit community, and there are already lots of things going on to support the family, and we just share our love and prayers with them, and we will continue to support them as they walk this path."
Dakota News Now identified the children's parents, Kelsey and Trevor Hupp. Rathburn told Fox News Digital that the parents were at work in town at the time of the explosion.
The house was located along South Dakota Highway 1806 in Stanley County. Dakota News Now said Bill and LaDonna were Trevor's parents.
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Kelsey Hupp wrote on a Caring Bridge page set up to provide updates on her two sons, 5-year-old Myles and 3-year-old Royce, who were airlifted to Regions Hospital in St. Paul, Minnesota. She said Myles has burns on 10% of his body, mainly first- and second-degree and was intubated.
"He squeezes my hand and wiggles his toes," Kelsey Hupp wrote. "He even fought sedation one time and sat up and looked around. He is stable."
Royce has 25% of his body burned with more severe third-degree burns on his chest and arms, his mother wrote. "He is also intubated and will be longer than Myles."
"The boys have a long road ahead of them, but we are just so thankful that we even have this road with them," she wrote. "They are strong and will persevere. I will do my best to update as I can because I know everyone cares. Please don’t stop praying. I’m going to need every ounce I can get to continue. We love our family, friends and community so much."
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A GoFundMe page established to raise money for the family raised more than $226,000 as of Thursday. It described "a tragic accident at the home of their dreams."
