More than 200 Red Shirt activists disrupted traffic in Bangkok Sunday to protest what they called the "twisted amendment" to the amnesty bill, the Bangkok Post reported.
The Red Shirts appeared at an intersection for a discussion at a nearby McDonald's restaurant where they used to gather right after the crackdown three years ago.
It followed a protest Thursday by the normally pro-government Red Shirts against the amended amnesty bill, the Post reported.
Protesters called the bill a "blank check" that would write off the debt to those who suffered violence at the hands of security authorities.
Thai Deputy Prime Minister Chalerm Yubamrung proposed the bill in April, saying it would heal the wounds of the past.
If passed by Parliament, all prisoners involved in political violence since the military coup Sept. 19, 2006, that toppled the government led by Thaksin Shinawatra, would be freed.
Amendments mean allegations against former Prime Minister Abhisit Vejjajiva, who led the Democrat Party and whom many people hold responsible for events during the 2010 crackdown, wouldn't be followed up.
A 73-year-old woman protester said she couldn't make peace with the ruling Pheu Thai Party for whom she voted, because of the blanket amnesty.
Thaksin, who lost power in the 2006 coup, was sentenced in 2008 to two years in prison for tax fraud, but fled Thailand rather than serve the sentence. He left an estimated $2 billion in frozen assets.
Since Thaksin left the country, his supporters have clashed with police many times, most notably in April and May 2010.
More than 90 people died and around 2,000 people were believed injured during the 2010 clashes when protesters blocked Bangkok's central old town streets for several weeks.
The fighting took place between security forces and the Thaksin-supporting Red Shirts and their political allies within the smaller United Front for Democracy against Dictatorship party.
The Red Shirts and their UFDD supporters were demanding the resignation of Abhisit and the reinstatement of Thaksin who often is credited with improving the financial situation of the poor, many of whom traveled into Bangkok to swell the ranks of the Red Shirts.
Supporters of Abhisit are called Yellow Shirts.
But the demonstrations turned violent when the army moved in to clear the streets.
The two-month extent and high number of deaths in the 2010 riots forced the government to set up a Truth for Reconciliation Commission.
Many Red Shirts would welcome the return of Thaksin, but abhor an amnesty for Abhisit who resigned after he lost the July 2011 election to Thaksin's sister, Yingluck Shinawatra.
Critics of her government claim her disgraced brother wields considerable political influence thanks to familial connections.
Yingluck gained a master's degree in political science from Kentucky State University in 1990 and was a successful businesswoman within the family businesses before becoming Thailand's first female prime minister.