Ezra 10:16-17

16 But the Banim of the Golus did so. And Ezra HaKohen selected anashim who were Rashei HaAvot for each of their father’s households, all of them by shemot. So they convened on the first day of the tenth month to investigate the matter.
17 And they finished investigating all men who had married foreign women by the 1st day of the 1st month.