CORONA (CBS) — An investigation has been opened into the death of a retired San Bernardino County teacher, who was accused of child molestation.

Darrell Ruppel, 65, apparently died of natural causes at about 9:15 a.m. Thursday at Corona Regional medical Center, coroner’s officials said.

Ruppel was arrested in October and has pleaded not guilty to six felony counts of lewd or lascivious acts with a child and one count of attempted sodomy with a person under 14 years old.

The charges stemmed from his time at Rim of the World High School near Lake Arrowhead in the late 1980s, according to the Riverside Press-Enterprise.

Ruppel was released on $750,000 bail Nov. 5 to the custody of a daughter who lived in Corona. According to San Bernardino County records, he was being monitored electronically.

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