A thief stole mail belonging to residents at six blocks of flats in Woodlands after a postwoman left a SingPost trolley unattended while using a restroom.
The theft took place at Block 734, Woodlands Circle last Thursday.
A SingPost spokesman said the postwoman did not take the postal items to the restroom three blocks away as it was raining heavily and she did not want them to get wet.
She tried to conceal the trolley with pieces of wood.
The postwoman discovered the trolley missing at 4.30pm and made a police report after conducting a search.
The SingPost spokesman said yesterday that it was "working closely" with the police and has notified affected residents.
It will also take disciplinary action against the postwoman, an employee of 17 years, for breaching "an established standard operating procedure" which forbids postal staff to leave mail unattended.
Ordinary mail is not tracked by Sing- Post so it cannot tell what items had been taken.
Residents told The Straits Times that they received a SingPost letter about the incident on Monday.
Housewife Maria Ratnam, 59, said she was concerned that some "important" letters may have been lost as a result.
"My husband is waiting for a court letter regarding a motorcycle accident he had," she added.
Neighbour Lau S.E., a 45-year-old teacher, said: "I don't even know what letters I missed. I may be charged with late payment for some bills I didn't even know I had."
SingPost said it was the first time a mail trolley had been stolen although mail had been left unattended in the past.
The Straits Times reported in June that a bundle of letters had been left unattended at a void deck in Toa Payoh with a note attached telling residents not to touch it and that a postman would return for it later.
SingPost said then that the postman had a heavy workload that day due to the haze.
As his storage box was full, he did not take all the mail with him to the next block. Disciplinary action was taken.
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