DUBLIN GAA stars were seen taking part in a training session in Dublin on Wednesday morning.
The Irish Independent is reporting that the group gathered before 7am on Wednesday at Innisfails GAA club on the northside of Dublin.
The Independent had images of the training session, with senior players including Jonny Cooper, Brian Howard and Brian Fenton seen to be taking part.
The training session came less than 24 hours after the GAA contacted every club and county across Ireland, and warned them that breaching the rules could put the scheduled return in "serious jeopardy".
Dublin GAA is yet to make an official comment, however, the GAA has said it is "extremely disappointed" to learn that this incident took place.
"The GAA will pursue the allegations with the units in question at the earliest opportunity and will invoke any necessary disciplinary processes as appropriate."
Inter-county teams were told this week by Taoiseach Micheál Martin that they would be allowed to resume training on 19 April.
GAA teams have not been allowed to train since the turn of the new year.
The Government recommendation for GAA's return from April 19 states: "Training for and playing of National Governing Body sanctioned and organised adult intercounty National Gaelic Games Leagues not including under 20 or minor competitions."
The earliest the first competitive games will take place is the weekend of 15 May.