Hours after a child reported being sexually assaulted at Ossington subway station, Toronto police announced an arrest in the case.

The mother of the boy told police that they were on an escalator heading toward ground level at around 8 p.m. when a man approached her seven-year-old son from behind and sexually assaulted him.

Police told CP24 that they received numerous calls about a man grabbing at children.

They said the callers indicated the grabbing was of “a sexual manner.”

"The mom did everything right. She went up to the collector’s booth, notified them, had them call 911, and she also had the time to pull out her cellphone and take a picture of the alleged suspect," Const. Victor Kwong told CP24 Thursday.

Police said that responding officers spoke to multiple witnesses a short time after the incident.

They believe the incident was random.

Investigators released a photo of the suspect on Thursday morning and by Thursday afternoon, confirmed that a suspect – identified as 41-year-old Chitranjan Boyal – had been arrested.

He is facing three charges including sexual assault, sexual interference and failure to comply with probation.

Boyal is scheduled to appear in court on Friday in Toronto.