In one such instance the chairman of the group received a death threat - on the day his wife died - stating that any potential investors "would not live to see the benefits of the sale".The Lagan Group was in discussions to buy the Aventas Rooftiles business in Fermanagh, which was formerly owned by the disgraced former billionaire Sean Quinn.However, because of the sustained attacks, the company has decided not to proceed.A spokesperson said: "Over the past number of months we have been engaging with the local workforce and management to secure a stable and sustainable future for the employees in the former Sean Quinn Rooftiles business now owned by Aventas."During this time various parts of the Lagan Group (and indeed businesses not connected to the group) have sustained a series of criminal attacks on property and plant causing substantial financial damage."These were executed with the sole purpose of creating a toxic atmosphere of fear and intimidation in order to illegally dissuade potential investment and investors into the area."We have repeatedly said that it was only a matter of time before such attacks switched their focus from property and plant to people."He added: "Last week on the day his wife died, Mr Kevin Lagan, chairman of the Lagan Group, received a letter containing a threat that should the Rooftiles business sale proceed, the purchasers "would not live to see the benefits of the sale"."No business can be expected to operate under such duress when normal operational decisions could result in putting employees, directors and their families at personal risk."Notwithstanding our desire to grow and invest in the Fermanagh rooftiles operations in order to support local communities through the maintenance of existing jobs and the creation of new jobs, we have decided to withdraw from the purchase process."We have informed the Aventas management team of our decision."This is a sad day for both the employees and for the local communities."It also sends out completely the wrong message to potential investors, both regionally and internationally."Justice Minister David Ford has described the threat as "totally unacceptable".The Alliance minister added: "Ongoing attacks on businesses formerly owned by the Quinn group serve only to put the jobs of current employees at risk and are to be condemned. The PSNI and An Garda Siochana are co-operating closely to bring those responsible to justice."The perpetrators should be in no doubt that they will be pursued by the police."