Patna, Jan 6 (IANS): Unidentified armed men carried out a robbery here Monday night by breaking into a house and injecting the family with sedatives before fleeing with cash and valuables worth lakhs of rupees, police said Tuesday.

The robbers entered the house of Jai Prakash Asthana in Patna's Jaiprakash Nagar and administered a sedative to his wife and two domestic help. They looted cash and valuables worth lakh of rupees, a district police officer said.

Asthana, who runs a private school in Bihar's East Champaran district, was not in the house when the robbery took place.

Police said the criminals entered the house after spraying some drug on four children, who were standing outside. Thereafter, they tied hands of Jai Prakash's wife Priyanka, and domestic help Sunita Devi and Dhaneshwar using plastic strings, injected them with sedative and escaped with cash and valuables.

Before injecting these three, the robbers forced them to hand over keys of the locker in which jewellery and cash had been kept.

Patna senior superintendent of police Jitendra Rana said that a case has been filed against unidentified criminals and an investigation launched.