In Imielin (4-5 September), 28 Poles were killed; in Kajetanowice (5 September), 72 civilians were massacred in revenge for two German horses killed by German friendly fire; Trzebinia (5 September), 97 Polish citizens; Piotrków Trybunalski (5 September), Jewish section of the city was set on fire; Będzin (8 September), two hundred civilians burned to death; Kłecko (9-10 September), three hundred citizens executed; Mszadla, Łódź Voivodeship (10 September), 153 Poles; Gmina Besko (11 September), 21 Poles; Kowalewice, Łódź Voivodeship (11 September), 23 Poles; Pilica (12 September); 36 Poles, 32 of them Jewish; Olszewo, Gmina Brańsk (13 September), 13 people (half of the village) from Olszewo and 10 from nearby Pietkowo including women and children stabbed by bayonets, shot, blown up by grenades, and burned alive in a barn; Mielec (13 September), 55 Jews burned to death; Piątek, Łódź Voivodeship (13 September), 50 Poles, seven of them Jews. On 14-15 September about 900 Polish Jews, mostly intelligentsia, were targeted in parallel shooting actions in Przemyśl and in Medyka; this was a foreshadowing of the Holocaust to come. Roughly at the same time, in Solec Kujawski (14 September), 44 Poles killed; soon thereafter in Chojnice, 40 Polish citizens; Gmina Kłecko, 23 Poles; Bądków, Łódź Voivodeship, 22 Poles; Dynów, two hundred Polish Jews. Public executions continued well beyond September, including in municipalities such as Wieruszów County, Gmina Besko, Gmina Gidle, Gmina Kłecko, Gmina Ryczywół, and Gmina Siennica, among others.
Question: What cities suffered murders on September 13th?
Answer: Gmina Brańsk | Mielec | Łódź Voivodeship