Police in Christchurch want anyone to come forward who may have taken photos or video of two fires in December that are being treated as arson.
One destroyed the Billens Building in High Street, which was a heritage building. The other was at the Konica Minolta building in Moorhouse Avenue.
Both fires happened on 7 December, between 9.20pm - 10.10pm.
Both sites were seriously damaged in the earthquakes. The Billens building was being strengthened, but the Konica Minolta building was being demolished.
Police said the fires appear to be have been deliberately lit.
Detective Gary Absalom told Summer Report they are hoping someone has heard something during Christmas gatherings which might give them a lead.
He said somebody's life may be put at risk if more fires are lit.