A publicity stunt by an underdog in the race to be governor of Bangkok went badly wrong when her campaign manager drowned as they bathed in a canal to highlight the plight of residents who have no access to clean water.

Candidate Leena Jangjanya said 32-year-old Thirasak Sitanont drowned on Thursday as she and other staff were showing journalists the rashes they got from washing in the filthy water.

"One of my staff saw him waving and crying for help, but we thought he was pretending and he was far away from us, posing for two TV crews," a sobbing Leena told Reuters.

"A few minutes later he disappeared and we had to call the police to come and find him," said Leena, who had fallen into another canal in front of the TV cameras on Wednesday as she was trying to show her support for riverboat commuters.

Leena, a businesswoman, is among 16 candidates in the race to be governor of Thailand's capital city of 10 million people.

She said she had suspended her campaign for the Oct. 5 election to help arrange a funeral for Thirasak and look after his wife, who is seven months pregnant. "If I were to continue to campaign after his death, I would be no better than an animal," she said.