SINGAPORE, Dec 13 — Around 20 people were evacuated from a property along Orchard Road in Singapore on Tuesday evening after white powdery substances were discovered in an envelope inside a mailbox.

The police and the Singapore Civil Defence Force (SCDF) confirmed to The Straits Times that they were alerted to the incident at 42 Saunders Road at approximately 5:30pm on December 12.

The road was cordoned off to allow SCDF officers in protective gear to retrieve the envelope, while hazardous materials specialists conducted tests on its contents, the report added.

Preliminary examinations revealed no immediate danger, but the substances are believed to be drug-related, according to the police.

As a precautionary measure, about 20 residents from neighbouring units were temporarily evacuated. No injuries were reported.

The case has been handed over to the Central Narcotics Bureau for further investigation.