A grenade was found by a sanitation worker on Thursday while he was cleaning a drain under a walkway in southwest Delhi's Sagarpur area, police said.
After receiving information, the police rushed to the spot and found an old corroded grenade with its pin intact. The district ballistic team safely placed it away from the crowded area in an open space, a senior police officer said.
The area around the grenade was buttressed using makeshift sandbags and police guards were stationed at the spot, the officer said.
The officer said the NSG has been urged to ascertain the make and model of grenade.
"The ballistic expert of the district could make out that it is 'HE 36' but rest of the details are not visible. This will be ascertained as soon as the NSG detachment arrives," Deputy Commissioner of Police (southwest) Ingit Pratap Singh said.