Archaeologists made a discovery in Vladimir, that ignites imagination. They found five bodies, not properly buried, but lying in a little hole, covered by the a layer of ashes. There were no signs of the violence. Then two more bodies were found. Preliminary analysis says that they belong to women and children and dated by 13th century.
On 7 February 1238, the Mongol army led by Batu Khan captured and sacked Vladimir, a city some 200 kilometres east from Moscow (more about these events in the articles: February 7 in Russian history and Russian history 33: Tatars and Batu Khan).
So, a plausible version of the events that led to the death of these people goes like this. When Batu Khan came to Vladimir, he destroyed the nearby villages. Five women and two children tried to hide in this cavity under the oven. When the fire started, the house fell and entombed them alive. Probably, they suffocated in the smoke. The cause of death and exact dating will be established during the investigation held by the Moscow Institute of Archaeology.
Source (in Russian): Во Владимире нашли захоронение восьмивековой давности.