Between 12.10am and 12.30am on Friday (October 19) seven vehicles parked on the side of Gibsons Green were set alight causing irreparable damage.
The vehicles were empty at the time.
Officers are particularly keen to speak to a grey haired woman about 5ft 8ins tall carry what looked like a washing up bowl who was seen in the area at the time.
Investigating officer PC Lewis Jones said: “I am appealing for anyone who may have seen or heard anything suspicious around the time of the incident or has CCTV footage that covers the area on Gibsons Green.
“I would really like to hear from the woman described above who was seen in the area at the time as I believe she may have information that is vital to our investigation.
“If you believe you have any details that may assist with this investigation, call 101 quoting reference 43180319545. Alternatively you can contact Crimestoppers anonymously on 0800 555 111.”