Northern Ireland's First Minister Peter Robinson has been involved in heated exchanges at the Stormont Assembly with rival unionist politician Jim Allister.
Mr Robinson accused Mr Allister of secretly being involved in selling land to Republicans, as executor of a will, to benefit his own family.
Mr Allister described the claim as "a damnable lie".
He later went to the private office of Mr Robinson and demanded that the request be withdrawn.
The two men were once political colleagues in the DUP.
With Mr Robinson's support in 2004, Mr Allister succeeded Ian Paisley as the DUP's representative in the European Parliament.
But they fell out over the DUP's decision to enter a power-sharing administration with Sinn Féin.
In 2007, Mr Allister departed to form his own Traditional Unionist Voice organisation.
At Stormont this afternoon, the row flared when Mr Allister sought to question Mr Robinson about his decision to pull back from supporting the planned peace centre at the Maze Prison.
The policy shift, announced last month, has caused difficulties between the DUP and Sinn Féin.
Mr Allister, as well as leading Ulster Unionist party members, have accused Mr Robinson of making a U-turn.
This evening, Mr Allister released a statement saying his wife was one of six beneficiaries of a will, following the death of her brother in Co Fermanagh last year.
In a repeat of what he had stated in the Stormont Chamber, Mr Allister said false allegations had been made against him by Mr Robinson.