Police said Surender (35) and his cousin brother Ravi, natives of Pratapgarh in Uttar Pradesh, were walking in the colony around 9.45 pm yesterday when a man riding a motorbike allegedly started abusing them.
And when they objected to the biker using abusive language, he called his accomplice and "the duo attacked us with bricks and stones", Ravi told police.
A passerby informed the police after seeing the brothers lying on road injured, a senior police officer said.
"A case of murder, attempt to murder and criminal conspiracy against two unidentified persons has been registered at New Colony police station and a hunt is on to nab the culprits. We have scanned CCTVs installed at a fuel station nearby to establish their identities," Gurgaon Police PRO Ravinder Kumar said.