Armed and masked intruders stormed a house near Fox River on the West Coast this week, just over a month after another "sinister" home invasion in the area.
About 9.30pm on Wednesday, offenders entered a main road property on State Highway 6, just north of the Fox River bridge, detainingthe occupants, a man in his 60s and his partner, for some time; one suffered minor injuries.
Both were left traumatised and have required counselling from Victim Support.
Tasman police communications manager Barbara Dunn said details of the incident were "still sketchy" as police had yet to interview one of the victims.
"We are unsure as to how many offenders entered the house, but we do know they disguised their appearance and there was definitely a firearm involved.
"This was a very serious incident and we want to hear from anyone who can help us apprehend the offenders. We want information, no matter how insignificant people may think it is."
Ms Dunn said anyone who drove along that stretch of road on Wednesday and saw a vehicle, either stationary or moving, should contact the police. The offenders left the property in a vehicle.
"Even if they saw nothing, we want to hear from them," she said.
Detective sergeant Gavin Nichols of Greymouth CIB said a scene examination would be carried out over the next couple of days with the assistance of ESR specialists.
Woodpecker Bay resident Muriel Donald heard about the home invasion from a friend.
"It is all a bit scary. After that (earlier) incident in Barrytown, it looks like rural properties are being targeted. It is one thing for offenders to burgle baches, which does happen a bit out here, but for armed people to break into homes and keep people captive is very, very alarming."
The two men involved in the Barrytown home invasion on May 9 are still at large. Police today could not say whether they thought the two might be linked.
Then the two men, armed with rifles, barged into the Barrytown address in the early hours, confronting the three occupants and leaving one of them with minor injuries.
