Tenants at JEM mall, where a ceiling collapsed about two hours ago, are still locked out of the building.

Many are anxious to lock up shops that were abruptly abandoned after a large chunk of the first-floor ceiling fell on Wednesday evening.

The portion of the ceiling that collapsed stretched from the entrance close to BreadTalk and extended to clothing store Lowry's Farm.

"I'm waiting to go back in because I haven't locked up for the day," said a second-floor boutique owner who declined to be named.

Said another basement store owner who wanted to remain anonymous: "This will definitely affect business. After the two previous fires there was already a lot of bad publicity".

The mall remains cordoned off by Singapore Civil Defence Force officers.

Individuals with vehicles still in the carpark have been allowed to retrieve them only through the carpark's entrance with the assistance of Police officers.

Three people were injured on Wednesday night after a portion of first floor ceiling collapsed suddenly.

A burst water pipe is believed to have been behind the incident, which occurred just after 10pm in the Jurong East centre.

Developer Lend Lease did not respond to queries as of midnight.

Singapore Civil Defence Force received a call for assistance at 10.14pm. Three people were taken to National University Hospital with minor injuries. One was seen being assisted by SCDF officers.