Police are no longer looking for a suspect alleged to have committed a sexual assault in Niagara Falls, Ont., concluding it didn't happen.

"Following a thorough and extensive investigation, detectives have found that the alleged assault did not occur, and the investigation has now concluded," Niagara Regional Police Service said in a news release.

On Monday, police said they were looking for a suspect after they received a report there was a break-in at a residence and a woman was sexually assault last week. Police had asked the public to come forward with information and surveillance footage, and described a suspect with "dark brown skin."

On Wednesday, police announced the search was off.

"Based on the investigation, none of the reported occurred," NRPS spokesperson Stephanie Sabourin said in an email to CBC Hamilton on Thursday.

CBC Hamilton had asked police why they no longer believe the assault occurred and whether the person who reported it retracted the allegation.

Sabourin said only that detectives made their decision following an investigation that included interviews and reviewing video.

Niagara police are committed to "investigating all allegations and providing support to victims and survivors," she said.

Sabourin was also asked what fact checking went into the original allegation and how police plan to address the possible consequences of a false report, but no comment was provided.