(SPRINGFIELD, Mo., AP) — Missouri prosecutors say a man imprisoned for a 2013 strangling had raped a woman days before the killing but avoided arrest by claiming the sex was consensual.

Greene County prosecutors charged 27-year-old Sean David Roberson on Tuesday with first-degree rape. Online court records don’t show whether he has an attorney.

Court documents allege that in March 2013, the alleged rape victim secretly left a note in a Springfield convenience store, saying she had been kidnapped and attacked. Investigators say the note asked for help and gave Roberson’s address.

Police notified about the note questioned Roberson but made no arrest. He insisted the sex was consensual.

Roberson is serving a 15-year sentence for manslaughter in a Branson strangling that took place six days later.