A 94-year-old retired External Affairs Ministry official was attacked and his 88-year-old wife stabbed to death during a robbery bid at their home in southwest Delhi's Safdarjung Enclave, police said on Sunday.
BR Chawla and his wife Kanta Chawla lived alone after the death of their two children a few years ago.
The incident took place around 9 PM on Saturday when the recently-appointed security guard of their building arrived at their home with his two-three associates, the police said.
According to police, the security guard and his associates barged inside the Chawla house, overpowered the couple and forced them to sit on a sofa.
When Kanta tried to resist the robbery bid, one of the accused stabbed her with a sharp object. She became unconscious and fell on the sofa, a senior police officer said.
The men then went to their bedroom and managed to flee after taking away all the cash and jewellery kept in their cupboard, he said.
While his wife was lying injured, the man managed to go outside the house to alert the neighbours who informed the Residents Welfare Association president.
The woman was taken to a nearby hospital where she succumbed to the injuries, he said.
A case has been registered and teams have been formed to nab the culprits, police said, adding that CCTV cameras are also being scanned.