Police said retried principal Subash Arora and his wife Kamlesh Arora, a retired government school teacher, used to live in the house in the densely-populated Islamabad area as their two sons were settled abroad.
They were killed with sharp-edged weapons, police said.
Police said that so far no arrest has been made. Police are trying to identify the accused with the help of footage of CCTV cameras installed outside the house.
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