Wellington  - A murder suspect was at large Monday, 24 hours after New Zealand police cordoned off about 15 square kilometres of North Island farmland and launched a manhunt.

Police said armed officers had searched outhouses, barns and wool sheds in rain and near-freezing temperatures and used heat-seeking helicopters without finding any trace of the suspect they named as David John Bourke, 46, from Wanganui.

They said the body of a middle-aged man was found in the crashed car of the suspect, who also shot and wounded a farmworker near the small town of Norsewood, 215 kilometres north of Wellington, Sunday.

Police commander Russell Gibson said officers were searching a huge area and warned farmers to stay indoors and be patient.

"We are dealing with a very dangerous person and we still believe he is in the cordon area," he said. (dpa)