Father, 2 sons trapped in silo die

POTTER TOWNSHIP, Pa. (KDKA) - A man and his two teenage sons were killed after they were trapped in a silo on a farm in central Pennsylvania.

Emergency crews were called to the farm on Lower Brush Valley Road in Potter Township, Centre County around 8:30 Wednesday morning, CBS affiliate WTAJ reported. 

The coroner's office said 47-year-old Andrew Beiler and his 14- and 19-year-old sons were pronounced dead at the scene, reportedly from asphyxiation due to gases in the silo, WTAJ reported. Their deaths were ruled accidental.

Neighbors told WTAJ it was a "ripple effect," with one going in to help the next.

Six months ago, a 16-year-old boy was killed on the farm while operating a manure spreader, WTAJ reported.