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.