A dozen inmates at Waikato's Waikeria Prison are facing misconduct charges - after being caught with homemade liquor on Christmas Eve

10 of the inmates are now in solitary confinement - and two have been moved to other prisons.

Prison general manager Jim Watson says the unit was temporarily locked down - but is now operating as usual.

He says no staff or inmates were injured - but the behaviour's unacceptable.

Watson says the prison will continue to carry out regular searches for contraband.

Waikeria Prison says home brew can be made with rotting fruit, water, sugar and a plastic bag.