A 35-year-old woman allegedly hacked her cousin to death on Saturday on suspicion that she was having affair with her husband in Madhya Pradesh's Shahdol district, the police said.
The incident took place at Padhkar village, 45 km from the district headquarters.
The accused was identified as Roshani Kewat.
Roshani suspected that her cousin Lalita Kewat (30), who lived nearby, was having affair with her husband, said inspector Mahendra Singh Chauhan of Budhar police station.
"Roshani lost her cool when she saw Lalita talking on mobile phone. She thought Lalita was speaking to her husband. She picked up an axe lying nearby and hit Lalita in the neck thrice, killing her on the spot," the officer said.
Later she allegedly told the police that she suspected that Lalita was having affair with her husband.
"We have arrested Roshani for murder," inspector Chauhan added.