The probe will examine consolidated financial statements of the contractor for the year ended 31 December 2019.

BDO resigned as nmcn’s auditor in July 2020 after ten years in the role.

Results for 2019 showed increases in pre-tax profit to £10.3m on turnover up at £404m.

But within 18 months estimated losses had hit £43m leading to the contractor’s fall into administration earlier this month owing suppliers more than £60m.