Niddah 7:3

All bloodstains from the city of Rekem are ritually clean (because they’re from the non-Jewish residents). Rabbi Yehuda rules them unclean because of converts who make mistakes. Bloodstains from non-Jews are ritually clean, while those from Jews and from Samaritans are ritually unclean according to Rabbi Meir. The Sages rule them clean as the Samaritans are not suspected regarding bloodstains.

Niddah 7:4

Bloodstains found anywhere are ritually clean except for those found in rooms or around a house of ritually-impure people. A Samaritan house of impurity conveys uncleanliness through overshadowing because they would bury miscarriages there. Rabbi Yehuda says they didn’t bury them; they would discard them and animals would carry them away.