SINGAPORE - The projectile that shot out from the 23rd storey of a skyscraper in Beach Road has been found to be a gas canister from a fire extinguishing system.

The system had been dismantled for disposal, said a spokesman for the building's management, the Singapore Land Group, on Wednesday (Aug 11).

Such canisters typically weigh between 10kg and more than 400kg.

It is believed the cylinder may have been left for several days near a window, where it was exposed to higher temperatures.

It had burst in a vacant unit at The Gateway West at about 10.30am on Tuesday, smashed through the window and ricocheted off the ground floor courtyard before crashing into the glass panels on the opposite building, The Gateway East.

The buildings are about 50m apart. No injuries were reported.

A spokesman for the Singapore Land Group, which initially said the object was a fire extinguisher, said it conducted an inspection with the Singapore Civil Defence Force (SCDF) on Wednesday.

The canister was part of an FM200 fire extinguishing system which the tenant had engaged a contractor to dismantle. Such systems are not typically found in normal office environments, but are commonly used for server rooms.

In the event of a fire, the system discharges a gas that is stored in a liquefied and highly compressed form in canisters.

Tenants at The Gateway have been issued a circular from the management about the incident.

SCDF said they were not called in to the incident on Tuesday.

But an inspection team was sent following the report by The Straits Times.

The iconic Gateway is a 37-storey skyscraper complex designed by architect I.M. Pei, who most famously designed the Louvre Pyramid in Paris.

It was completed in 1990 and is known for its trapezoidal shape that gives the illusion of being two-dimensional when viewed from certain angles.

The incident on Tuesday left a gaping hole in the side of The Gateway West on the 23rd storey.

ST has contacted the Workplace Safety and Health Council for comment, and has asked Singapore Land Group for more details regarding the incident.