According to legend:
The last vengeance took place in the year 946 when Olga traveled around the land of the Drevlyans in order to gather tributes. She besieged the town of Iskorosten, which refused to pay her. According to legend, the Princess asked that each household present her with a dove as a gift. Then she tied burning papers to the legs of the doves and let them fly back to their homes. As a result, the entire town was destroyed by fire.
Wikipedia has the same story, but with sulphur.
The Drevlians begged for mercy and offered to pay for their freedom with honey and furs. She asked for three pigeons and three sparrows from each house, since she did not want to burden the villagers any further after the siege. They were happy to comply with such a reasonable request. Now Olga gave to each soldier in her army a pigeon or a sparrow, and ordered them to attach by thread to each pigeon and sparrow a piece of sulfur bound with small pieces of cloth. When night fell, Olga bade her soldiers release the pigeons and the sparrows. So the birds flew to their nests, the pigeons to the cotes, and the sparrows under the eaves. The dove-cotes, the coops, the porches, and the haymows were set on fire. There was not a house that was not consumed, and it was impossible to extinguish the flames, because all the houses caught on fire at once.
Clearly, this is exaggerated. However, is it a feasible method of burning down a house and is there any evidence that this event actually occurred?