The watchdog said girls as young as 11 "expect" to have to perform sex acts on rows of boys for up to two hours at a time in parts of London, according to her research.
She also said it was "quite common" for girls to be lured via internet chat rooms to meet a friend, only to be met by a group of boys and gang raped in a park.
"In urban, rural and metropolitan areas, I have hard evidence of children being sexually exploited," she said.
"That is part of what is going on in some parts of our country. It is very sadistic; it is very violent it is very ugly."
Car parks were among the places where the sex abuse took place
During the gang's trial at Liverpool Crown Court it emerged they had plied the girls with fast food, drink and drugs so they could "pass them around" and use them for sex.
The men, who are all from Pakistan except one man who is from Afghanistan, targeted white, vulnerable girls.
The abuse happened in and around Rochdale in 2008 and 2009 and centred around two takeaway restaurants which are now under new management.
One 13-year-old victim fell pregnant and had the child aborted. Another teenager recalled being raped by two men while she was so drunk she was vomiting over the side of the bed.
Nine men were found guilty. One cannot be identified for legal reasons
Colin Lambert, the leader of Rochdale Borough Council, told the committee it was wrong to say the problem was linked to a specific racial group.
"It's too easy to badge a crime. It takes away from the crime itself where you can say 'it only occurs in this particular community'", he said.
The victims of the Rochdale gang were all described by police to have come from "chaotic", "council estate" backgrounds.
Kabeer Hassan, Abdul Aziz, Abdul Rauf, Mohammed Sajid, Adil Khan, Mohammed Amin, Abdul Qayyum, Hamid Safi and a 59-year-old man who can't be named for legal reasons were jailed for a total of 77 years.
The Independent Police Complaints Commission is currently investigating a series of mistakes by Greater Manchester Police and the CPS for failing to take the first victim seriously when she first reported the abuse.
She carried on being targeted by the gang until December 2008 when she fell pregnant and moved away.