Up to 60 cars and properties are reported to have been damaged in the Rhwbina Hill area of Cardiff last night.
Local residents said they woke to find vehicles badly damaged after being hit by what they said was a stolen van.
South Wales Police is investigating and said officers were called to Caer Wenallt area around 11pm last night following reports of a white Transit van deliberately being driven into a 'large number' of parked vehicles.
No-one was hurt during the incident.
Police say the van, stolen from the Newport area, was abandoned nearby and the occupants made off.
Officers are carrying out house to house and CCTV enquires in order to identify those responsible.
Anyone with information is asked to call police on 101 or Crimestoppers anonymously on 0800 555 111 quoting *021353.