Tauranga police have seized cannabis plants and other suspected drugs in an operation targeting a rural house in the lower Kaimai Ranges.

The armed offenders squad swooped on the house in Ruahihi Road around 6am.

Police closed nearby State Highway 29 for public safety, believing there were chemicals used to manufacture methamphetamine inside the house. The road was completely closed for about an hour.

Detective Sergeant Darryl Brazier says they recovered a number of cannabis plants and some white powder, which is yet to be analysed. Police also found instruments believed to be used for making P.

A 38-year-old man is helping police with their inquiries.