City police chief Rusdi Isa said the 48-year-old victim had been on holiday in Malaysia for two months.

He said the woman is believed to have been swept away by strong underground water currents.

“It is understood that tomorrow was supposed to be her last day in the country,” he said at a press conference.

The victim was walking from Selangor Mansion to Lebuh Ampang at 8.22am when the sinkhole opened up on the sidewalk, burying her underground.

“Witnesses saw what happened, but did not see much movement (in the sinkhole) after that,” said Rusdi, adding that land subsidence had occurred nearby last year.

Search and rescue (SAR) efforts for the victim are ongoing, with a total of 90 personnel across various agencies being deployed.

Rusdi said the SAR requires careful planning as it involves public infrastructure, adding that various factors – including the underground gas conditions – need to be considered.