Horowhenua District Council has cancelled planned Matariki celebrations in Shannon

It says there's an ongoing police incident unfolding, and people in the area should stay inside.

A spokesperson told our newsroom they're saddened by the impact one individual can have on a community joining to celebrate what was meant to be a joyous event.

Police have confirmed a person's been arrested - but are yet to provide further information.

A St John spokesperson says they've sent two ambulances, a rapid response vehicle and management unit.