Sita Divari, who is also a spokesman for the party, said the man was not a party canvasser as alleged by the People's Alliance for Democracy (PAD).

The anti-government group claimed a one-legged man assaulted an anti-Thaksin group demonstrating outside the plaza. It claimed the man was a campaigner for a Khlong Toei politician.

The mysterious man is said to go by the name of "Pae Khlong Toei".

Sita denied the individual was his aide and said he did not recognise the person from pictures.

Caretaker senator for Bangkok Prateep Ungsongtham agreed. She  questioned why Khlong Toei residents were slandered as gangsters.

Prateep is founder of the Duang Prateep Foundation, which works in the Khlong Toei slums. She said people there had become political victims because they were considered uneducated, poor and gullible.

She did not believe Sita hired Khlong Toei residents to assault anti-Thaksin demonstrators.

"The PAD has often accused Khlong Toei people of assaulting its supporters. This is not fair," she said.