Businessman Sean Quinn has described attacks on his former companies as "offensive and unacceptable".
In a statement issued last night, Mr Quinn (pictured) said he was repeating his family's position, which is the total condemnation of any act of intimidation.
It comes after workers at a company operating wind farms, previously owned by the Quinn group, received bullets in the post.
Business editor of the Sunday Business Post Tom Lyons said the motivation for the attacks was unknown.
He said: "There have been suggestions that (the people who sent the bullets) have links with former paramilitaries, or are just crazy individuals.
"We don't know what is behind the attacks. We know issues have been raised locally around rights of way and access to land where the wind farms are...But, none of those people are saying they are doing the attacks."