Police staff and patrol cars are intentionally being rammed every second day across the country

An internal police document released to OneNews raises serious concerns that vehicles have become the weapon of choice.

This week alone, three patrol cars were rammed after a driver attempted to escape police in Lower Hutt.

Police Association President Chris Cahill says an officer is hospitalised every month because of an injury in a ramming.

Mr Cahill says many of those involved are quite young offenders which adds to the difficulty.