A Davenport, Iowa man being held on kidnapping and rape charges recently sent a threatening letter to his victim with some help from his father.

The Quad City Times reported that Nathan Ronnau, 29, now faces a charge of first-degree harassment along with charges of first-degree kidnapping and second-degree sexual abuse.

On July 1, Ronnau allegedly choked his ex-girlfriend into unconsciousness, dragged her into a wooded area and raped her. Police said the victim regained consciousness and struck Ronnau. He then beat her.

Ronnau told officers he was drunk and didn't remember what happened.

On July 27, the victim's daughter found a threatening letter taped to their apartment door. In the letter, Ronnau warned "all hell will break loose" if the victim is dating another man.

"I don't care how long it takes for me to get out. You don't want to know how or what I will do if I find out you've been with another man," he wrote.

Police said Ronnau's father delivered the letter, but was not aware of its contents.

Ronnau faces a life in prison and is being held in jail on $1 million bond.

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