A 65-year-old woman and her son were held hostage at gunpoint and robbed by four men at their home in Anand Vihar area of east Delhi on Saturday morning, police said.
The son identified as Ashish Dhawan (40), a contractor with the Delhi Metro, suffered injuries on his head after he was attacked by the butt of a countrymade revolver.
The incident was reported at 4:45 am on Saturday, when Dhawan and his mother Pushpa were sleeping on their second-floor home in Dayanand Vihar.
The other members of the family had gone to attend a wedding in Pitampura. Police said the accused beat up Dhawan, tied his hands and legs and locked him in the bathroom, before fleeing with cash and valuables.
"They barged into the house after breaking open the main door. They ransacked the house and beat up my son. They spared me when I begged before them that I was old and harmless," said Pushpa Dhawan.
After the accused left the scene, the old woman unlocked the bathroom and rescued her son. A call was made to the police control room and he was rushed to a nearby hospital.
Police said they have registered a case of robbery and were investigating the matter.
"We have recorded the statements of both the victims and are investigating the case," said IB Rani, deputy commissioner of police (east).
Police said the accused must have had some information about the cash and valuables at the house and struck accordingly.