Fifteen gardai in Limerick are being quizzed over suspected road traffic offences which were not prosecuted.
Officers from the National Bureau of Criminal Investigation seized documents, paper and computer records in a number of searches during the week.
A Garda spokesman told the Irish Mirror: “We can confirm an investigation into alleged Garda corruption and wrong doing in the Munster area is currently underway.
“It is not the policy of An Garda Síochána to comment on third party comments.”
GAA top brass are to discuss claims a senior garda intervened to ensure prosecutions against officials and players did not proceed.

It has been alleged cases of road traffic offences, criminal damage and a drink-driving related matter were either abandoned or not followed up on properly.
Sources close to Limerick GAA said players and officials are “keeping their heads down, it’s very shocking”.
One added: “There’s a full county board meeting involving all of the clubs on Tuesday night.
“There will be a management meeting on beforehand and without a doubt this will be raised.
“There will be an obligation on the top table to make some kind of a statement on it, to bring clarity. Everyone is in shock.”
The allegations were carried in Sunday newspapers. It’s reported the searches form part of a wider inquiry into alleged garda corruption which is being led by gardai attached to the National Bureau of Criminal Investigation.

However, there is no evidence directly linking officials or players to the NBCI probe, which is concentrated on alleged collusion between gardai and criminals.
Three gardai have been suspended as part of the wider probe.
“The Limerick players are going on their team holiday next weekend to Barbados. They’re going for about ten days. This is casting a shadow over that,” added the GAA source.
Limerick hurling sponsor JP McManus has organised the luxury trip, which will see the entire squad and their partners visit the McManus-owned prestigious Sandy Lane resort.

The allegations have tainted the joy which followed the team’s historic All-Ireland win last year, ending the county’s 45-years in Liam MacCarthy wilderness. The source added: “It is a pity that this is now the topic of the conversation among everyone.”
A second source close to the County Board said: “A few people knew about this. I believe the players were interviewed and their phones were (examined), and that happened I think around Wednesday or Thursday.”
“The Board, in general, have been told nothing, but there’s a meeting of management on Tuesday night so it will surely come up at that.”
“I think every officer on the Board is entitled to know what is going on,” they said.
The sources also confirmed they were aware of speculation “during the summer” surrounding some players, but that nothing had come out of it.
“I think all officers should be made aware of what’s going on, and hopefully on Tuesday night we will be told – we will be asking anyway,” said the second source.
“There is shock. I think the rumours are coming to the surface now, whether there is more (to come) I don’t know,” they added.
Members of the Limerick County Board did not respond to requests for comment.