A loud blast shook the house of a senior Thai opposition leader overnight, police said on Wednesday, as protesters trying to oust the government remained camped in central Bangkok with no end to the political deadlock in sight.
Some hardline protesters have threatened to blockade the stock exchange and an air traffic communications facility on Wednesday if Prime Minister Yingluck Shinawatra does not step down.
But there were no early signs of trouble at either the bourse or at the central Bangkok offices of AeroThai, which is in charge of air traffic control for planes that use Thai air space.
(Read more: Thai protesters move to shut down Bangkok)
No one was hurt in the blast at the residence of Democrat Party leader and former Prime Minister Abhisit Vejjajiva.
"There was no one at home at the time. The explosion destroyed part of the roof of the house. It wasn't a bomb. We believe it could have been a big firework," said an officer at the nearby Thong Lor police station, declining to be named.
Abhisit and other Democrat leaders have joined in the protest movement against Yingluck, and have refused to take part in an election she has called for Feb 2.
She has invited leaders of the protest movement and political parties to a meeting on Wednesday to discuss a proposal to postpone the election, but it looked like only her allies would turn up.
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The unrest is the latest chapter in an eight-year conflict pitting the Bangkok-based middle class and royalist establishment against the mostly poorer, rural supporters of Yingluck and her brother, Thaksin Shinawatra, a former premier ousted by the military in 2006 who is seen as the power behind her government.
Abhisit was prime minister in 2010 when troops were sent in to end a two-month protest in central Bangkok by Thaksin supporters. More than 90 people died during those protests.