Harleen Maggo and her paternal grandparents Ragvir Kaur-Kainth, 82 and Pyara Kainth 87, died in the tragic incident late on Saturday night.
Initial investigations by the police revealed that the accused husband, who also had another wife, had sent his other wife to India with his two children before committing the crime.
The woman in Andhra Pradesh's Kakinada took the extreme step following domestic unrest, police said.
The leopard has been killed by the locals, a police official said.
An Indian-origin man has been charged with stealing more than $250,000 in a Ponzi scheme in which his friends and coworkers invested.
Debashis Ghosh, 54, of Chicago and Keith Eric Jergensen, 58, of Salt Lake City, Utah, were convicted in October 2017 of wire fraud conspiracy.