An Invercargill speed camera operator has been seriously assaulted.

The incident happened just before 8.20pm on Friday (29 April).

The camera operator was sitting in a red-coloured van, parked in the northbound lane on Dee Street, Invercargill, near Thames Street.

"Our investigation has established that a person riding a motorcycle has stopped a short distance away from the van before approaching it," said Inspector Jon Bisset.

"The person, who was not known to the camera operator, has then used a metal object to smash one of the van's windows which resulted in the victim being struck and receiving moderate injuries.

"This was an extremely serious and distressing incident for our Police employee and he was fortunate not to have received more serious injuries."

The camera operator is now recovering at home.

Police would like to hear from anyone who witnessed the assault or observed a motorcycle in the area at this time. 

Anyone with information should contact Police on 105 and quote file number 220403/0506.

Information can also be provided anonymously to Crime Stoppers on 0800 555 111.