A Casper man is accused of more than a dozen sex crimes with four different under-aged victims.

Forty-five year old William Hall has pleaded not guilty to four charges of second degree sexual abuse of a minor, four charges of third degree sexual assault, four charges of immoral or indecent liberties with a child, and two charges of sexual exploitation of children.

Investigators with the Natrona County Sheriff's Office say through interviews with one victim, Hall had her take nude photos of herself with his cell phone, and then later threatened to distribute the pictures if he wasn't allowed to perform certain sexual acts on her.

Those incidents are alleged to have taken place between March and August 2015.

Investigators later found several Department of Family Services reports, where Hall was suspected of having sexual relations with three other victims, between 1999 and 2002.

Two of the victims said they engaged in various sexual acts with Hall a number of times in Glenrock, in exchange for alcohol.

When interviewed by DFS back then, Hall admitted to having sex with one of the girls and knew it was wrong, but said it was consensual.

As for the remaining victim, she said her family moved in next to hall in Natrona County, and one night, Hall took her rabbit hunting, got her drunk and had sex.

She estimated having about 50 encounters with Hall in a two year period.

Hall is being held on $100,000 bond awaiting trial, and could face up to 20 years in prison on each second degree sexual abuse of a minor charge, up to 15 years on each third degree sexual assault charge, up to 10 years on each sexual exploitation of children charge and between five-to-12 years on each immoral or indecent liberties with a child charge, if convicted.