WorkSafe is investigating how a worker was "seriously injured" while cleaning at Claymark's Rotorua sawmill

The agency says the incident occurred while a worker was cleaning a chain conveyor in the early hours of the morning, this week.

Workers First Union says the accident is extremely worrying - considering a trainee machine operator also had two fingers amputated there in 2023.

Worksafe's investigation into that incident found the machine was unguarded and there was an ineffective system for maintenance.