Nisha Mahendra (56) was shot dead last night around 11.30 PM when her son-in-law Raman Beniwal fired from his licenced weapon during a dispute at the victim's flat at Rana Pratap Bagh in Bharat Nagar area, a police official said.
Raman, a resident of Ashok Vihar, had been married to Chandni for 12 years and they had two daughters. He was apparently an alcoholic and the couple used to have frequent fights over the issue, he said.
After one such fight, Chandni left for her parents' house yesterday following which he went there to persuade her, he added.
Nisha tried to intervene but the accused took out his licensed pistol, aiming at his wife, but his mother-in-law was hit by the bullet instead, he said.
Raman fled from the spot after the incident. Family members rushed the victim to a nearby hospital where doctors declared her dead.
A case of murder has been registered and teams have been formed to arrest the accused, the officer added.