The Krasowo-Częstki massacre was a Nazi war crime perpetrated by the Ordnungspolizei and SS in the village of Krasowo-Częstki within occupied Poland. On 17 July 1943, the village was completely burned; 257 of its inhabitants, mostly women and children, were murdered. The massacre was an act of retaliation against the civilian population, after at least eight Germans were killed in a skirmish with Polish partisans in the nearby colony of Kalnik. It was the bloodiest pacification action conducted by Nazi-German occupiers in those areas of prewar Białystok Voivodeship, which after Second World War remain within the borders of Poland.