Two south Delhi homes less than 200 metres from a Kalkaji Extension police station were burgled on Wednesday morning, police said.
It took the assailants only two hours to smother an 86-year-old man to death in one house, seriously injure a 76-year-old woman in the other and escape with cash and valuables worth Rs 4 lakh.
The incidents were reported from the homes of Janakraj Likhi, a retired ministry of Information and Broadcasting under secretary who was murdered, and Vidya Gulabani, a retired schoolteacher.
"Prima facie, it seems the assailants dismantled a make-shift iron grill between the first and ground floors at Gulabani's residence," a police officer said.
The assailants then entered Gulabani's ground floor room and attacked her, the officer said.
An hour later, an unconscious Gulabani, bleeding profusely from her left cheek, was found lying on the floor by grandson. The assailants, meanwhile, "seem to have climbed over to Likhi's house, the officer said.
Likhi was killed because the robbers were allegedly unhappy with just the Rs 8,000 to 10,000 they found in the house.