Ngawha prison filling up

Northland's new Ngawha prison now has 265 inmates - 85 short of the 350 maximum it was built to hold.

Ngawha site manager Mike Hughes said the prison, which opened in March, was on target to be full by the end of October.

Meanwhile, investigations are continuing into what caused a 4mm-wide crack in the wall and ceiling of a building last month.

Critics of the site have warned about its proximity to the Ngawha Springs geothermal field.