Protests in several provinces and a late-night blast in Bangkok deepened the sense of crisis as Thailand’s political stand-off continued.
In the capital, a grenade attack on the home of a law-maker allied to the ruling coalition injured eight people.
Outside Bangkok, red-shirt protesters were reported to have blocked roads to prevent police reinforcing colleagues.
The red-shirts have been camped out in Bangkok since 14 March. On Sunday the PM rejected a new offer of talks.
The reds want the government to step down and call fresh elections. On Friday they gave a 30-day window for the government to dissolve parliament – a shift from their demand for immediate dissolution.
But Prime Minister Abhisit Vejjajiva appeared on television on Sunday with the army chief to reject the red-shirts’ offer.
“There must not be a precedent that allows intimidation to bring about political change,” he said.