A religious leader who founded a celebrated organisation for people with learning difficulties sexually abused six women in France, an internal report says.
Canadian Jean Vanier set up the global network L'Arche in France in 1964 and died last year aged 90.
None of the women he abused was herself disabled, the report says.
An investigation into Vanier was commissioned by L'Arche International last year after suspicions were raised.
"We are shocked by these discoveries and unreservedly condemn these actions, which are in total contradiction with the values Jean Vanier claimed and are incompatible with the basic rules of respect and integrity of persons, and contrary to the fundamental principles on which L'Arche is based," the current leaders of L'Arche International, Stephan Posner and Stacy Cates Carney, wrote in a letter to the L'Arche Federation.
"We recognise the courage and suffering of these women, and of any others who may not have spoken up...
"We ask forgiveness for these events which took place in the context of L'Arche, some of which were caused by our founder."
The organisation runs homes and centres where people with and without disabilities live together, operating in 38 countries with around 10,000 members.
What does the report say?
Vanier, a devout Catholic, had "manipulative and emotionally abusive" sexual relationships with six women in France, between 1970 and 2005, according to a statement by L'Arche International.
Sexual relations were instigated by Vanier, usually in the context of giving spiritual guidance.
"These women reported similar facts associated with highly unusual spiritual or mystical explanations used to justify these behaviours," the statement said.
"The relationships [...] had a significant negative impact on their personal lives and subsequent relationships.
"These actions are indicative of a deep psychological and spiritual hold Jean Vanier had on these women," it said.
It also says Vanier asked the women the keep the incidents secret.
The women included assistants and nuns, according to Canadian newspaper the Globe and Mail, which first broke the story.
Vanier was also a member of a small clandestine group which subscribed to and participated in some of the deviant sexual practices of disgraced priest Thomas Philippe, the L'Arche statement said.
The practices were founded on so-called "mystical" or "spiritual" beliefs that had been condemned by the Catholic Church, it added.
Vanier described Philippe, who died in 1993, as his "spiritual father", but publicly denied knowledge of the practices.
The investigation was carried out by independent UK consultancy GCPS.
Who was Jean Vanier?
The son of a Canadian diplomat, he left a naval career in 1950 to study theology, saying he wanted to "follow Jesus".
While visiting a chaplain in Paris who worked with men with learning difficulties, he became disturbed by the poor conditions in which the men lived.
He founded L'Arche - the Ark - to provide communities for people with learning difficulties to live alongside people without disability as equals.
There are now 154 L'Arche centres around the world.
Vanier was nominated for the Nobel Peace Prize for his work, and was awarded the prestigious Companion of the Order of Canada.
In 2015, he was the recipient of the Templeton Prize, an award described as "entirely deserved" by the Archbishop of Canterbury, Justin Welby.