AVON and Somerset Police are investigating allegations of assault involving two employees of a West Country plant hire firm.
The allegations centre on a dispute last week between the pair at Frome-based Blackbird Plant Hire.
Bulldozer driver Patrick Dewaine claimed he was attacked following a row on site.
Mr Dewaine, 58, from Llandeilo in South Wales, said he was beaten around the head so severely that he had to be taken to Frome Hospital.
He said: 'I am suffering from double-vision and pains in my head. I have been in this game since 1959 and nothing like this has ever happened to me before.'
Blackbird declined to comment on the incident.