An investigation is underway after two objects were lit and thrown into the yard at the Palmerston North Police Station overnight.
The impact caused minor damage to two vehicles.
Police say this will not affect resourcing or deployment in the area.
"The investigation team is reviewing CCTV footage and police ask anyone with information about this incident to call 105 or Crimestoppers anonymously on 0800 555 111," a spokesperson said.
