POTTSVILLE — The operator of an eastern Pennsylvania coal mine has been sentenced to prison and the owner to house arrest in connection with a mine explosion that killed a man three years ago.

Fifty-three-year-old David Zimmerman and his son, 34-year-old Steven Zimmerman, both pleaded no contest to involuntary manslaughter last month. They were charged in the death of 43-year-old Dale Reightler of Donaldson, who died in a methane blast in October 2006.

The defendants also pleaded guilty to recklessly endangering another person and three violations of the Anthracite Coal Mining Act.

Judge Jacqueline Russell sentenced Steven Zimmerman to three to 23 months in prison and David Zimmerman to six months of house arrest.

State prosecutors called the case the first successful manslaughter prosecution in a mining death in the commonwealth.

The defendants said nothing during Wednesday's hearing, but Assistant Public Defender Lora McDonald, Steven Zimmerman's lawyer, said her client is remorseful.