The dead man has been identified as Suthin Tharatin, and a spokesman for the national police force said Tharatin had been shot in the head and the chest. Amateur footage (above) purported to show the moment he was killed.
The shooting brings the death toll in Thai anti-government protests since November up to 10. Protesters are calling for Yingluck Shinawatra, the Thai prime minister, to step down. She is accused of being a proxy for her brother, ousted former premier Thaksin Shinawatra.
Ms Yingluck called a national election for 2 February – an election she would be expected to win because of a large rural support base. However, the largely middle class and royalist supporting protesters are opposed to this.
Early voting was due to take place in 50 polling stations across the Thai capital on Sunday – but protest action saw 45 of these polling stations closed.
Bangkok police said clashes broke out across the city between anti-government protesters and supporters of Prime Minister Yingluck’s government. Both sides were reported to have been trading punches, before shots were fired.
The Erawan Medical Centre, which monitors Bangkok hospitals, said 11 people were hurt in the clashes in the Bang Na district.
It was not clear who fired the shots, but protesters have accused the government and police of trying to intimidate them.
“The government has allowed thugs to use weapons,” Akanat Promphan, a spokesman for the protesters, told reporters.