VALLEY SPRINGS (CBS13) – The Calaveras County Sheriff’s Office is investigating what may have caused the deaths of twin brothers who died after their life support machines failed during a power outage.

On Tuesday at 4 p.m., deputies responded to a call in the 5000 block of Rippon Road in Valley Springs where 22-year-old twin brothers Josh and Ryan Hall were in respiratory distress. Deputies started CPR on the men and requested assistance from EMS personnel, but they still died. The twins had long suffered from muscular dystrophy, which required them to be connected to breathing ventilators and had them bound to wheelchairs.

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Neighbor Betty Barron saw medical crews outside the Halls’ home after the power outage, which lasted at least an hour.

“It’s just unexpected, like I feel really sorry. It’s something really sad, losing the kids,” said Barron.

The sheriff’s department says it has no information connecting the twins’ death to Tuesday’s PG&E power outage in Amador and Calaveras Counties, according to Sgt. Chris Hewitt. However, a family friend told CBS13’s Ian Schwartz the battery packs on the breathing ventilators failed after the power went out.

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“She’s a very nice person,” said Barron. “She devoted her whole life to the children. I mean, who wouldn’t?”

Neighbor Jodi Coffelt says she is stunned about the tragic deaths, hoping the best for the family.

“I don’t have any thoughts; it’s just really sad, really said. My regards go to Julie,” she said.

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Detectives say the twins’ mother was at the scene and cooperated with investigators. The cause of the twins’ death has not yet been determined.