Protesters in Thailand on Saturday demanded that Prime Minister Abhisit Vejjajiva call elections within 15 days or face big street demonstrations.
Thai media said 30,000 supporters of the United Front for Democracy against Dictatorship were at Government House, which was occupied for three months last year by a rival protest group, the People's Alliance for Democracy.
UDD leaders say they also want the PAD prosecuted for the occupation of Government House and Bangkok's two airports last year.
The march ended a month of relative calm in a three-year political crisis, which has distracted policymakers from dealing with an economy close to recession.
