It truly is a shame to see this sort of internal violence in Thailand as it seems so out of character for the country.
Scuffles broke out and a woman was punched in the face when five pro-government supporters were grabbed and held by People's Alliance for Democracy (PAD) guards who claimed they were armed and ready to incite violence.
The incident has turned up the heat between the rival camps as tensions mount ahead of the United Front of Democracy Against Dictatorship's (UDD) next big rally on Saturday.
Political emotions have grown increasingly hostile since the PAD shut the door on proposals by academics for peace talks with the UDD.
Observers believe the Kwam Jing Wan Nee (Truth Today) mobile political talk show in Bangkok on Saturday will attract a huge crowd of UDD supporters as former prime minister Thaksin Shinawatra is expected to address the rally by phone from London.
Concerns are mounting the talk show could stir up emotions and create a volatile atmosphere among UDD supporters.
In what many fear could be a taste of things to come, a group of UDD supporters in red shirts were intercepted on Tuesday by the PAD guards outside the alliance's protest venue at Government House.
Four women and one man wearing red shirts with the words "Choose Samak, Love Thaksin", were caught early in the afternoon in a pick-up stuck in traffic.
The PAD guards claimed a few young men in the back of the truck fired slingshots at them. The guards were manning a protest checkpoint near Nakhon Sawan Road. They alleged one UDD member tried to hit them with an axe, but missed.
The young men escaped and the PAD guards grabbed five people in the front seat. They paraded them on the PAD stage in Government House and said the five were UDD supporters.
PAD demonstrators reacted with fury and tried to grab the five before the guards hustled them out of the grounds.
During the chaos, a male guard reportedly punched one of the women, Sombat Khayanchoomnoom, 53, in the face. She fell to the ground with her face bleeding.
Some of the PAD guards alleged Mrs Sombat and the others were carrying petrol, a knife and an axe and intended to attack PAD protesters. The UDD members denied the claim.
The guards said they found a red flag with the words "The Truth Today Show" and a cap saying "Saturday People Against Dictatorship" in the truck.
The five UDD supporters were handed over to police for questioning.
Tuesday's incident was the second involving UDD and PAD supporters. On Sept 2, they clashed near Makkawan Bridge on Ratchadamnoen avenue resulting in the death of a UDD supporter.
In the scuffle, the PAD guards were accused of taking the five and beating them near the protest security check point called the "PAD Station".