The three accused, identified as Vijay, Jaspal and Pala, were arrested after they brutally killed their sister, Nargis, on July 16 in Mari Buchian village near here, police said.
The victim got married to Ravi, a resident of the same village, two years ago, the officials said.
Nargis' brothers, however, were not happy over the relationship. Meanwhile, initially the couple started living outside the village but they came back a month ago.
Following this, on July 16, Nargis' brothers went to her in-laws' house along with their aides and allegedly murdered her with sharp-edged weapons, they added.