Ottawa police have laid two aggravated sexual assault charges and two choking charges on a 41-year-old man after women in the sex trade spoke to officers during the investigation into the unsolved homicide of Amy Paul.

The investigation into Jacques Leonard Rouschop began during the probe into the unsolved September homicide of Amy Paul. Her partially-clothed body was discovered in a south Ottawa hay field on Sept. 17.

Amy Paul suspicious death victim field

The body of Amy Paul, 27, was discovered in a farmer's field Sept. 17. She had been reported missing earlier that month. (Facebook)

Paul, 27, worked in the sex trade and she lived hand to mouth on the street, police say.

During their investigation into her death, which continues, officers interviewed dozens of people including other women working in the sex trade.

Two of those women told police they had been sexually assaulted by Rouschop, which led to the charges being laid against him. He is already in custody on another matter.

Rouschop appeared in court via video Monday wearing a purple golf shirt. His next court appearance is scheduled for Jan. 7.

Ottawa court records show Rouschop has a lengthy criminal history dating back at least two decades.

The investigation into Paul's death continues. On Thursday, police announced a $50,000 reward for any information leading to an arrest and prosecution in the case.

Ottawa police have been warning women in the sex trade about a pattern of violence since 2011.