SINGAPORE — Nearly three hours after the Woodleigh MRT station was closed today (April 18) because of the discovery of a "suspicious substance", authorities gave the all-clear for the station to reopen at 4.20pm.

The suspicious substance found at Woodleigh MRT Station was later determined to be baking flour.

Dozens of officers from the Singapore Civil Defence Force's hazardous materials (hazmat) team and the police had responded to the incident earlier.

TODAY reporters on the scene saw at least one SCDF hazmat vehicle, a fire engine and at least four police vehicles outside Woodleigh station. A few members of the public were seen milling outside the shuttered gates to the station.

Speaking at Woodleigh MRT Station shortly after the station reopened, Member of Parliament for Potong Pasir SMC Sitoh Yih Pin said: "Much as we always hope that nothing will happen, we must always be prepared in case anything happens."

"Thankfully, the station is opened (before the peak hour). So our residents won't be too inconvenienced," Mr Sitoh added.

A 58-year-old cleaner on the morning shift, who did not want to be named because she is not authorised to speak to the media, told TODAY in Mandarin that she spotted some white powdered substance near a board at the station as she was about to leave for lunch.

She did not recall seeing the substance when sweeping the floor at about 7am on Tuesday, and decided to inform the manager of the Woodleigh station just after noon.

Earlier, at 1.49pm on Tuesday, transport operator SBS Transit said the station on the North East Line was closed as a result of a "security incident". Free bus rides are available at bus stops between the Serangoon and Potong Pasir stations.

This is the second security incident reported at a MRT station this month. On April 2, a 39-year-old man who left an unattended bag at Hougang MRT station sparked security fears and a brief shutdown of the station.

He was arrested and subsequently released on police bail while investigations continued. The man, who has not been identified, reportedly left his luggage bag unattended and went off to run an errand. The police found only household items in the bag. — TODAY