A birthday party turned into a nightmare for a businessman's family here on Sunday night when five masked men with firearms barged into their residence, held them hostage and looted cash and jewellery worth around Rs. 7 lakh.

The incident was reported from the Vivek Vihar residence of Surender, where he hosted a party to celebrate his grandchild's birthday around 10:30 p.m., a senior police official said on Monday.

The robbers knocked on the door and when it was opened barged inside. The masked men had firearms and knives and wore gloves. The revellers were huddled into a room and a gun was placed on the head of a girl. They were threatened that the girl would be shot dead if they raised an alarm, the official said.

While some of them kept a watch on the hostages, he said, the others ransacked the house. According to the family, robbers took away about Rs.5 lakh cash and jewellery and other articles worth around Rs.2 lakh.

The robbers locked them in a kitchen before fleeing from the spot besides taking away mobile phones of all of them to ensure that they could not contact anyone," the official said.