The law-enforcement bodies are considering, in particular, such versions as carelessness with fire or arson.
A decision on possibly filing a criminal case will be taken following the check.
The fire in the preserve was extinguished on Thursday. According to the latest information, roughly 300 hectares of woodland burned down. A strong wind hindered the extinguishing of the fire. Possible hotbeds of a new ignition are now under observation.
The Lazo wildlife refuge has a total area of 121,000 hectares. In the past few years about 150 hectares a year on average burned down there during the whole fire-hazardous period (spring and autumn), director of the preserve Alexander Laptev said.
The Lazo wildlife refuge has populations of Amur tiger, goral and sika deer.