The members of YesCymru's Central Committee have announced that they have "collectively resigned and stood down from their roles with immediate effect".
In a letter sent to members, the Central Committee said that "an independent, third party firm of accountants" has been instructed to "oversee limited day to day operations of the organisation" until a new Central Committee is elected at a forthcoming Extraordinary General Meeting.
The Central Committee said that the decision had "not been made lightly", but was "taken in the best interests of the organisation."
The Central Committee said that "harassment directed towards Central Committee members, that goes far beyond social media posts, has taken an incredible toll on mental wellbeing and can no longer be tolerated."
The outgoing Chair of the Central Committee, Sarah Rees, said: “The accountancy firm will focus on helping the Gweithgor and YesCymru staff to organise the forthcoming EGM and electing a new Central Committee. This decision has been taken in the best interests of the organisation and its members. It enables a totally clean break from the past and provides a clean start for the newly-elected Central Committee in the autumn, while protecting all the good that has been created.
“YesCymru now has 18,000 members. It only officially launched five years ago. It is a fantastic success story, and testament to the hard work of ordinary members in growing the demand for Welsh independence. The decision taken today gives the new Central Committee, with the support of all 18,000 members, the opportunity to take YesCymru to the next level.
“I would encourage all members of YesCymru to attend the EGM and to vote for a new Central Committee which reflects the type of movement you want to be a part of - this is your chance to shape the direction of YesCymru for the better and we wish the new Central Committee every success.”