A Thai protester was gunned down and three others wounded in a drive-by shooting in Bangkok early on Saturday, just hours before candidates around the country began signing up to contest in snap polls on Feb 2.
Later, in five southern provinces where the opposition Democrat Party has considerable support, protesters converged on the registration venues and forced Election Commission officials to suspend the process.
In Bangkok, however, registration proceeded smoothly. There was no sign of the protesters who had occupied government buildings and clashed with police on Thursday, leaving two dead.
Most candidates who signed up were from the ruling Puea Thai party. The opposition Democrat Party is boycotting the election, saying the process is corrupted and will inevitably bring the Puea Thai, which is seen as a proxy for former Thai premier Thaksin Shinawatra, back to power.
Registration is due to continue through Jan 1.
In Chiang Mai, Thaksin's brother-in-law and former premier Somchai Wongsawat said he was confident the registration process would be completed.
"The candidates have five days to register. And this morning, 90 per cent of the registrations took place," he told The Sunday Times while observing the process in Chiang Mai.
The Puea Thai had sent a candidate to contest in every seat in the country, he said.
The protester who was shot and killed yesterday was a member of a student network that had joined protest leader Suthep Thaugsuban's self-styled People's Democratic Reform Committee (PDRC).
The shooting was seen by analysts both as a message to the group, and as a signal of increasing tension and volatility.
Political science professor Panitan Wattanayagorn of Chulalongkorn University, once a spokesman for Democrat Party leader Abhisit Vejjajiva, said that even if the registration process failed in five provinces, it would not necessarily scuttle the election or force a postponement.
The issue for the Election Commission, he said, was whether the election could be conducted in a free and fair environment without violence.
Analysts said the Election Commission is itself split on whether to conduct polls. Some election commissioners have hinted that they may resign if the government does not accept a delay. The government has said it will simply appoint new commissioners in their place.
Many Thais have left Bangkok for the holiday season. After Thursday's clash, which left two dead and 153 injured, Thailand's powerful army chief on Friday warned the warring sides to exercise restraint.
After taking pains to remain neutral, army chief General Prayuth Chan-ocha said for the first time that he did not rule out an army takeover, warning that he was flashing the equivalent of a "red light" to both sides.
Saturday's relative calm however may be a lull before the storm resumes, analysts said. Mr Suthep has called for a massive protest to shut down Bangkok after the holiday period ends on Jan 2.
"What happens in Bangkok after the New Year break may actually determine what happens to the election," Professor Panitan said.
Suthep's People's Democratic Reform Committee has attracted Thais from all walks of life, but its backbone is the relatively wealthy Bangkok middle-and upper-middle class elites.
The Committee wants the Premier to resign, and for an appointed 400-member, unelected "people's council" set up to institute reforms before a return to electoral democracy.
The Puea Thai has rejected this and, confident of its own mass support mainly in the populous north-east, insists on going ahead with snap polls.
It has proposed instead an independent reform council, dismissed by the committee as toothless.
The committee sees Ms Yingluck Shinawatra as a puppet of her billionaire brother, who was kicked out of office by the army in 2006 on grounds of corruption and disrespecting the monarchy.
In the medium-term, another Puea Thai victory at the polls is unlikely to solve much.
"Those who are anti-government may be just a few million, but they are powerful and they will not give up easily," said Prof Panitan.
Additional reporting by Tan Hui Yee in Chiang Mai
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