A farmer south of Auckland says crossbows should be treated like guns and require licensing.
David Olsen, who farms at the southern end of the Hunua Ranges, said three of his cows were found on Sunday with arrows protruding from them, and one was dead.
Mr Olsen said the police only turned up more than three hours after he and his wife had repeatedly called them.
"It's an offensive weapon, a crossbow, they should be licensed just like a gun licence, they can do just as much damage, and of course they don't need a silencer or anything like that on them."
Under the Crimes Act, crossbows were classified as offensive weapons, but people did not need a licence to use them.
Police were investigating the case.