BANGKOK - Thailand's prime minister called on anti-government protesters Sunday to give a "clear answer" by the following day on whether they will end their mass rally in the heart of Bangkok.
"You should stop the rally quickly for safety reasons," said Prime Minister Abhisit Vejjajiva, whose reconciliation "roadmap" aims to defuse a two-month confrontation and entails holding elections on November 14.
"Schools are about to open. Parents are concerned about their children's safety," he said on national television. "There should be a clear answer by tomorrow (Monday) so that cooperation on the reconciliation plan will go ahead."
Thailand's government and "Red Shirt" protesters on Saturday committed themselves to a peace process at risk of faltering after twin attacks left two police officers dead.
Grenade blasts and a drive-by shooting earlier targeted security forces locked in a stand-off with anti-government Red Shirts at their massive rally encampment, which has shut down most of Bangkok's main shopping district.
Both sides said the attacks were the work of groups intent on derailing Abhisit's reconciliation "roadmap", which is aimed at ending a two-month confrontation and entails holding elections on November 14.
The Reds have signed up to the peace process but are demanding a firm date for the dissolution of parliament before disbanding their base, where they are barricaded behind piles of fuel-soaked tyres and razor wire.
The overnight attacks also wounded 12 people, the latest outbreak of violence in a crisis that has left another 27 dead and nearly 1,000 injured in clashes and other explosions.
The government urged the Reds to end their campaign quickly to avoid further bloodshed.
"Some groups of people do not want to see (the plan) succeed so the government calls on the Red Shirts to quickly make a decision, otherwise there will be more casualties," government spokesman Panitan Wattanayagorn said.
Police said three grenades were thrown at a security checkpoint in front of a park that forms the edge of the Red camp. A 35-year-old policeman died in hospital and another five police and three soldiers were wounded.
Earlier, one policeman was killed and four others -- two police and two civilians -- were injured when a man on a motorbike opened fire on officers patrolling the nearby Silom financial district.
The Reds denied any involvement in the attacks, which they also said were carried out by elements intent on sabotaging the peace plan.
"This will not distract us or derail the process," said Reds leader Nattawut Saikuar. However, he indicated that an agreement was not yet within reach.
"The five-point roadmap plan which is proposed by Abhisit we already understand. But on our part, we need a few more days to come up with our own proposals, which will be flexible," he said.
Underlining the Reds' determination to remain at their fortified base, 5,000 more supporters arrived Saturday from the movement's heartland in Thailand's rural, impoverished northeast.
Crowds at the Reds camp have swelled to as many as 100,000 people in the past, but earlier this week when a resolution appeared near, numbers dwindled to just a few thousand as a weary air descended on the rally area.
Pro-establishment "Yellow Shirts" -- who blockaded Bangkok's two main airports in 2008 in their own protests -- have rejected the roadmap and election plan and called on the prime minister to resign.
And in another setback, a moderate pro-government group known as the "Multicoloureds", whose rallies in the capital have also drawn thousands of supporters, called for the election date to be pushed back.
In its colour-coded crisis, Thailand is largely split between the mainly rural poor and urban working class Reds -- who broadly support fugitive former premier Thaksin Shinawatra -- and the elite-backed Yellows.
The Reds condemn Abhisit's administration as illegitimate because it came to power in an army-backed 2008 parliamentary vote after a controversial court ruling ousted Thaksin's elected allies.
The billionaire ex-premier, who was ousted in a 2006 coup, now lives in exile to avoid a jail sentence for corruption.
European Union envoys in Bangkok called for a quick and peaceful resolution to the crisis following the latest unrest.
"We strongly condemn the recent acts of violence and express our condolences to the families of the victims," top diplomats from the EU and its member states said in a statement.
"We call on all sides to refrain from violence and hope that an early peaceful solution can be achieved to swiftly lead Thailand back towards national reconciliation, prosperity and stability, with full respect for the rule of law and democratic principles."