A 94-year-old retired external affairs ministry official was attacked and his 88-year-old wife stabbed to death during a robbery bid, allegedly by a personal security guard they had recently hired, at their home in south Delhi’s Safdarjung Enclave, police said on Sunday.

B.R. Chawla and his wife Kanta Chawla lived alone in the upper ground floor of the building. Their two children had died a few years ago.

The incident took place at 9pm on Saturday when the personal security guard arrived at their home with two or three of his associates, barged in, overpowered the couple and forced them to sit on a sofa, the police said.

They tied Chawla’s hands and legs with a rope. When his wife tried to resist the robbery bid, one of the accused stabbed her. She became unconscious and fell on the sofa, a police officer said. The men then went to the bedroom and escaped with all the cash and jewellery, he said.

Chawla managed to get out of the house and alert neighbours, who informed the Resident Welfare Association (RWA) president. Kanta was taken to a nearby hospital where she died, he said.

The couple had hired the guard with the help of their building security guard, who had worked there for 25 years. RWA president V.K. Malhotra, however, said the new guard was not registered with the police. The society is under 24x7 watch and has eight CCTV cameras.

Malhotra, who lives in the adjacent building, said the couple was registered with Delhi police’s senior citizen scheme.

A case has been registered and teams have been formed to nab the culprits, police said, adding that CCTV cameras in the area are also being scanned.