Quinn Derrylin headquarters damaged in lorry attack
Businessman Sean Quinn's former headquarters in Derrylin, County Fermanagh, have been damaged in the latest in a series of attacks.
Police have launched an investigation after a lorry was backed into the staff canteen on Wednesday night leaving a gaping hole.
The workers had gone home. No-one was in the building when it happened.
The attacks have happened since the former Anglo-Irish Bank took control of the business.
The lorry used in the latest attack was later found burned out on a side road.
Sinn Fein's Phil Flanagan said a digger and a bulldozer were also damaged at a quarry in Derrylin.
The Fermanagh and South Tyrone MLA said the attacks served no purpose and were "very worrying".
"They are not going to stabilise Quinn group or secure any jobs," he added.
Mr Quinn, 63, once believed to have been the richest man in Ireland, was reputedly worth 4.72bn euros (£3.7bn) at the height of his success.
He was stripped of control of his manufacturing and insurance business empire in April. Since then, there have been a series of attacks on Quinn Group properties.
Mr Quinn has previously condemned the attacks, and said those responsible for the damage were not acting in his name and called for them to cease.
He and his family are engaged in a legal battle with the Irish Bank Resolution Company (IBRC).
It has been in court this week attempting to have Mr Quinn's bankruptcy in Northern Ireland set aside.