Suspected child abusers were at "all levels" within scouting organisations and there is evidence some moved to other scout groups after allegations were made about them.
The latest revelations from a Scouting Ireland review of historical abuse claims have been described by the organisation as "deeply shocking and distressing for everyone involved in scouting".
Meanwhile, Children's Minister Katherine Zappone expressed "grave concern" at the soaring numbers of alleged victims and perpetrators being identified.
The figures now stand at 317 alleged victims and 212 suspected perpetrators over a period spanning 70 years.
Most of the cases date from the 1960s to the 1990s.
The number of reported victims has tripled in the three weeks since the scandal first emerged, as more people have come forward reporting abuse.
The scale of the alleged abuse was revealed after Scouting Ireland met gardai and Tusla, the Child and Family Agency, to provide an interim update on child safeguarding expert Ian Elliott's investigation into historical cases.
The allegations relate to former organisations the Catholic Boy Scouts of Ireland (CBSI) and the Scouting Association of Ireland (SAI).
A Scouting Ireland statement last night said: "Young people in the care of these organisations were abused, sexually and physically.
"The alleged perpetrators were at all levels within the organisations.
"There is evidence of alleged perpetrators being moved within scout groups.
"The stories emerging are difficult for those telling them.
"We are deeply sorry that anyone who would have expected to be safe in these organisations were not."
It sought to assure those who have come forward that Scouting Ireland is taking all allegations seriously.
Scouting Ireland, which was founded in 2004, said it "inherited this situation and is now dealing with its consequences".
It said it is working closely with gardai and Tusla to ensure all complaints against alleged perpetrators who are still living are investigated thoroughly and "appropriate action taken as necessary".
The statement said gardai have full access to all information held by Scouting Ireland.
Scouting Ireland said the organisation recognises the trauma suffered by the alleged victims and is providing counselling support for those who wish to receive it.
Emergency financial measures are being considered by the organisation to provide resources and support.
Scouting Ireland has revised its policies and procedures on the advice of Mr Elliott to strengthen safeguarding.
"The safeguarding of children and adults is the number one priority of the board and the executive team," it said.
"We thank those who have come forward and shared information with us.
"It means we can take action and become a stronger and safer organisation as a result."
Ms Zappone said the increase in the number of alleged victims and perpetrators "once again underlines the serious challenges facing Scouting Ireland".
She predicted the numbers coming forward will increase and said: "Supporting victims is my top priority.
"I would encourage anybody who has been abused or who wishes to name an alleged perpetrator to come forward."
The minister met with representatives of Scouting Ireland last month to discuss previous revelations that 108 alleged victims and 71 alleged abusers had been identified by Scouting Ireland.
The Scouting Ireland confidential freephone helpline is 1800 221199. Tusla's confidential helpline is 1800 805665.