A 41-year-old woman drowned in her pickup truck when it stalled in a 100-metre underpass at the entrance to the luxury housing estate where she lived in Prawet district early on Thursday morning.
Her tragic fate was reported to Prawet police about 2am.
Relatives told police that she phoned for help, saying the water in the underpass, beneath railway tracks, was about a metre deep and rising. She was trying to get out of the stalled vehicle. Then the phone signal disconnected.
Relatives rushed to the underpass, only to find it was filled with water. Rescue workers dived to the truck and retrieved her body at about 5.30am.
The underpass is the back entrance to the Golden Nakara housing estate.
The woman's name was initially withheld from the media, but she was later identified as Panumas sae Tae, managing director of Optimo Thailand Co, which runs property and cosmetic businesses. She was married to a Malaysian man.
Prawet district chief Thanasit Metpanmuang said the management of the housing estate had sought permission from the State Railway of Thailand to build the underpass for the convenience of residents.
It was equipped with a pump because it was often flooded in the wet season.
On Wednesday night the pump was turned off because the pipe broke. Shortly afterwards the woman reached the partially flooded underpass. The rapidly rising water stalled the vehicle's engine and filled the underpass before she could get out.
The underpass links the housing estate and a local road parallel to the Bangkok-Chon Buri motorway.