A woman was arrested in Karachi's Shah Latif Town for murdering her sister-in-law while "joking around".She said she strangled her while they were joking around. Latifa was arrested by the police an hour after the incident occurred on Thursday.Family members say she often fought with Rubina, her sister-in-law. But Latifa says on the day of the killing, they didn’t fight.Related: Aunt kills nephew in Gujrat because he was ‘cuter’ than her childrenWe were just joking around and I strangled her, she said. Sometimes she would do that to me and I would retaliate, she added. The woman also said they often verbally abused each other as well.A case has been lodged on behalf of the woman’s husband, Ghulam Hussain, at the Shah Latif Town police station.