The city police on Saturday arrested a 24-year-old man and his friend for allegedly killing his wife at Kalyan in Thane. Sanam Karotia, 25, was shopping in the APMC vegetable market on Friday afternoon when her husband Sachin Karotia and Deepak Thakur, 20, reached there on a scooter and one of them allegedly stabbed her with a knife several times, the police said.