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The former chief of staff to Sen. Lamar Alexander allegedly bought child pornography and tried to distribute it on an Internet site, according to a criminal complaint filed in the D.C. District Court today.

Ryan Loskarn appeared in a federal court in Washington this afternoon to be formally charged, a day after he was arrested on the charges and promptly fired by Alexander, R-Tenn.

The complaint alleges that between November 2010 and March 2011, Loskarn purchased child porn from a video company in Toronto, Canada, which mailed DVDs to his home. In October 2013, the U.S. Postal Inspector Service "identified Loskarn's residential IP address on the Gnutella peer-to-peer network offering files with names that are consistent with child pornography broadcasting as a download candidate," according to the complaint.

Loskarn is accused of then posting and attempting to share pornographic videos that depicted the sexual abuse of girls as young as 6 years old on an Internet site.

U.S. Postal Inspectors tried to enter Loskarn's home Wednesday morning with a search warrant. While inspectors tried to get into his home with a battering ram, Loskarn was seen looking outside a window of his home and placing an item on a ledge on the roof, authorities said.

"After approximately three to five seconds, Loskarn made a motion as if he were placing something down outside the window and closed the window," the complaint reads.

Inspectors later found a Toshiba hard drive on the roof. While Loskarn did not admit to placing the hard drive on the roof, he confirmed he owned a Toshiba hard drive, according to the complaint. A computer forensic examiner found pornographic videos of young girls as well as hundreds of sexually explicit videos of young boys on the hard drive, the complaint said.

Possession of child pornography carries a maximum penalty of 10 years in prison. Attempt to distribute child pornography carries a mandatory minimum of five years and a maximum of 20 years in prison.

A preliminary hearing is scheduled for Monday.

Loskarn was arrested by U.S. Postal Inspectors at his home Wednesday afternoon. Alexander immediately placed Loskarn on administrative leave when he learned of the investigation and removed him from his payroll later in the day.

ABC News' Jack Cloherty contributed to this report.