Shashi Bhushan Singh of Bihar was arrested from the residence of one of his relatives in Haryana's Faridabad Wednesday night.
He had attacked his brother-in-law Harender, 25, a transporter, and sister Priyanka, 23, with a sharp-edged weapon at their residence in west Delhi's Aman Vihar area Wednesday afternoon.
"Singh went to meet Priyanka at her residence where he took out a knife after a heated argument and attacked Harender. When Priyanka tried to intervene, he stabbed her also and ran away," said a police officer.
Harender died of his injuries while Priyanka is stated to be out of danger.
Police said three months ago, Priyanka eloped with Harender and married him. Priyanka's family was opposed to the marriage.
The incident came to light when neighbours found Harender and Priyanka in a pool of blood and informed police.
--IANS (Posted on 10-10-2013)