The Waterloo Regional Police Service has arrested a Milton man in connection with three separate sexual assaults against young girls that occurred between 2013 and 2019.

Insp. Mark Crowell said police made the arrest Thursday evening at around 5:30 p.m. in Milton.

Crowell said the man, 32, lived in Waterloo region during the first sexual assault in 2013 and the second sexual assault in 2017. The man was living outside the region, in the Milton area, when the July 6 assault happened.

Police said they continue to explore why the man was in Waterloo region at the time of the third assault.

"We continue to explore relationships and I can say he does have personal connections to this region that remain during that period," Crowell said, adding the man was a stranger to the children.

We won't rest until it's resolved.​​​ - Insp. Mark Crowell, Waterloo Regional Police Service

Though an arrest had been made, Crowell said, their investigation is not over and police still want to hear from any other witnesses or victims.

"This is the beginning of a new phase of the investigation, where we now can hone in on this individual and track movements over the years and to explore any linkages relationships or any aspects of the investigation that we've not yet uncovered," he said.

Insp. Mark Crowell with the Waterloo Regional Police service announced Friday that officers had arrested a suspect in three sexual assault investigations involving young girls in Kitchener and Waterloo. (Kate Bueckert/CBC)

Three sexual assaults since 2013

The man faces three charges of sexual assault and three counts of sexual interference and will appear in court in Kitchener on Friday.

The investigation started in October 2013 when a four-year-old girl was sexually assaulted in an apartment building on Barrie Place in Waterloo.

The second sexual assault happened on Oct. 27, 2017 at an apartment building on Patricia Avenue in Kitchener. In that case, a six-year-old girl had been playing outside with a friend around 7 p.m., police said.

The third sexual assault occurred on July 6. A four-year-old girl was sexually assaulted in the common area of an apartment building on Brybeck Crescent in Kitchener.

On July 24, police released a video of the man running on Karn Street toward Belmont Avenue in Kitchener at 8:15 p.m. on July 6, shortly after the most recent assault occurred.

In the photo the man was shirtless and wearing beige pants and fled the area in a grey, four-door 2016 to 2018 Honda Civic LX.

Crowell said the police service had all hands on deck for the investigation, with any available officers assisting where they could.

"When you have an unknown sexual offender, especially a serial sexual predator, involved in multiple linked cases, we provide every investigative avenue, every investigate resource we can to as quickly as we can resolve it," he said.

"We won't rest until it's resolved."