A man has been cut free by firefighters after his arm became trapped in a harvester in mid-Canterbury.

Emergency services were called to a property in Barhill between Methven and Rakaia just after 1pm.

A Fire Service spokesman said the man's arm had been caught in a harvester and had to be cut free.

He has been flown to Christchurch Hospital in a serious condition.

A St John's ambulance spokeswoman said the man was "very sick" by the time he was freed.

It is not known whether he has lost his arm.

- nzherald.co.nz