Leaders of the so-called "multi-coloured" group have pledged to gather every day to protest against the House dissolution being demanded by the red shirts.
Thousands of them gathered yesterday at the Royal Plaza, an inner Bangkok area near Government House and other government offices, choosing pink, white and other colours for their clothing.
Many of them waved national and yellow flags and listened attentively to speakers on a large stage. Yellow represents the colour for Monday which is His Majesty the King's day of birth.
"We plan to gather like this for two hours every day, from 4 to 6pm," said Tul Sitthisomwong, a doctor at Chulalongkorn Hospital, who has become a leader of the group.
He did not answer when asked whether the brief period of demonstrating, avoiding a night-time presence, was to steer clear of danger.
But he said there was a need for security after the Thursday night attacks at Silom when five grenades were fired into the anti-red shirt protesters, many of whom are believed to be supporters of the multi-coloured movement.
"We're worried about the safety of our protesters here. But whatever will happen, let it be," he said.
The group has communicated via the Facebook social networking website and showed up at public places over the past few weeks.
Today, they will gather at Suan Luang Rama IX Park in the early afternoon before gathering again at Chatuchak Park. They will then station themselves at Victory Monument for the next few days, said Dr Tul. Their key agenda is to end the protest of the red shirt United Front of Democracy against Dictatorship, he said. But other speakers who took to the stage whipped up the crowd's emotions by criticising the government's "weakness" for not doing something concrete to end the red shirt protest.
But even though they call themselves the multi-coloured people who want peace, yesterday's protest was reminiscent of the yellow shirt demonstrations of the anti-Thaksin Shinawatra People's Alliance for Democracy.
The way they dressed and acted as well as their agendas seemed little different from that of the PAD crowd - showing loyalty to the King, supporting the military and shouting their loathing for Thaksin and his supporters.
Gen Pathompong Kesornsuk, a supporter of the PAD who played a key role during the yellow shirt protest, also appeared on stage yesterday, getting both jeers and cheers from the crowd.
"I don't understand what the government is waiting for [by not dispersing the red shirts]," he said.
Despite other PAD core leaders not being present, those who took to the stage were from parts of society traditionally aligned with the yellow shirts: business groups, state enterprise workers' unions and middle-class Bangkokians.
Many held up images of the King as speakers urged the crowd to carry on protecting the royal institution. They gathered for about three hours and dispersed before dusk.
Kannika Detkong, 56, said she had been frustrated with the red shirt protest and the violence that had ensued. So she decided to show up yesterday.
"I'm not afraid that there might be violence here like that which occurred at Silom on Thursday night. Deadly violence has not deterred me from coming," Ms Kannika said.
"I wonder why the government has not dispersed the red shirt demonstration but is letting innocent people get injured and killed," she said.
Writer: Surasak Glahan and Sirikul Bunnag