An Alden man who had been serving as a foster parent even though he was convicted many years ago of child molestation was sentenced Tuesday by Chief U.S. District Judge William M. Skretny to 20 years in prison on child pornography charges.

Chad A. Salvatore, 40, had previously been convicted of distribution of child pornography, receipt of child pornography and obstruction of justice.

Assistant U.S. Attorney Aaron J. Mango said Salvatore downloaded child porn in December 2010 and later distributed it to an FBI agent in Rochester and to a federal agent with the Colorado Internet Crimes Against Children Task Force.

At the time of Salvatore’s arrest, investigators revealed that he had been acting as a foster parent to a young teenager, even though Salvatore had been convicted of molesting three children when he was a teenager.