Two people have died at a rural property in Masterton district as a result of gunshot wounds.

They were nice people, the neighbours said. They would smile and wave. They were not known to the law.

Yet at 5.15am on Monday shots rang out from the bucolic spot in Tinui, near the end of the road from Masterton to Castlepoint on the Wairarapa east coast.

Inside, a woman in her late 40s and a man in his 50s were dead. At least three others in the house - adults in their 20s - remained alive.

Robert Kitchin/Stuff Police at the scene of a double fatality on Masterton Castlepoint Rd, near Tinui.

The Armed Offenders Squad was deployed but armed police arrived first and figured they could safely enter. They cleared the home of the remaining people and took them away for questioning at Masterton Police Station.

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The house was guarded by police while they waited for forensic investigators from Auckland and Wellington to arrive.

Robert Kitchin/Stuff Police are likely to be at the scene for a number of days.

"We believe there is a firearm inside the address but we haven't located it," said Wairarapa area commander Inspector Scott Miller at the cordon outside. Police were fast to launch a homicide investigation.

Inside too were the two bodies. They were two people who knew each other, though quite how remained unclear.

Outside, just hours later, unshorn sheep munched grass, as unperturbed by the sudden police and media presence as they were by the rusty blue tractor in thier paddock.

The white brick, single-storey house where two people had died appeared well-cared for. The grass was mown and the flowers were in bloom. It bore no exterior hallmarks of the violence of Monday's dawn.

Miller confirmed the people were not known to police, meaning they were not known criminals. No-one else was being sought by police in relation to the deaths, he said.

Nearby a neighbour talked of the nice people who had moved into the house no more than 12 months before. They would smile and wave but that's what people did in the area.

"They were good people, what I knew of them," he said.

A man who lived close to the scene woke up on Monday to armed police outside his house.

"They are sitting outside my place now. They had their guns out. Looks like they are doing a waiting game," he said early on Monday morning.

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