In the early hours of 13 December eight motorbikes in Columbus Street were set alight.
The blaze was so intense that it shattered the windows of a nearby house and left two women, aged 24 and 32, trapped inside.
They were rescued by firefighters and treated for minor injuries.
The police have now released a picture of two men walking along nearby Dorset Street at around 3 am on the same night, shortly after firefighters were called out.
Detective Inspector Steve Langford, of the States police Criminal Investigations Department, said that the two men were not currently suspects but officers would like to speak to them to see if they have any information.
Anyone with any information is being asked to contact police on 612612 or Crimestoppers on 0800 555 111.