Thailand's anti-government"red- shirts" hold rally Saturday afternoon to call for release of the UDD leaders and members being held at prisons across the country.

Led by the United Front for Democracy against Dictatorship (UDD) chairperson Thida Thawornsret and co-leader Jatuporn Promphan, the group read out letters of complaint from their detained leaders.

On the mobile rally stage, Jatuporn, also an opposition Puea Thai party-list MP, said Saturday's rally was the biggest ever demonstration of the "red-shirts."

Thida, whose husband, as a key figure of the movement, was also imprisoned since the protest dispersal on May 19, criticized the government for unfair treatment against the detained UDD leaders.

The Puea Thai list MP said at the Democracy monument rally stage late this afternoon, he would provide facts to the general public about who were behind the killing of people at Ratchaprasong intersection and set fire to several department stores in May.

Jatuporn said if the detained UDD leaders are not released on bail as request, on March 12 UDD will once against call for another mass gathering.

During March and May 2010 the "red-shirt" movement had held a prolonged protest in a bid to oust Abhisit government from the office. As the government resorted to military forces to disperse the protesters on April 10 and May 19, 91 people were killed and nearly 2,000 injured. The UDD then regularly organizes rally on 10th and 19 of every month to commemorate their deceased members.

Following the end of the demonstration, about 19 UDD leaders have been detained on the charge of terrorism. Soon after the forceful dispersal on May 19, several buildings, including banks, a theater, department stores, a building of stock market exchange of Thailand, were set ablaze.