BANGKOK — Gunmen killed an anti-government activist and wounded two others in Thailand's capital on Saturday, while protesters elsewhere blocked candidates from registering for upcoming elections, deepening a political crisis that threatens to derail democracy in the Southeast Asian nation. The registration for the Feb. 2 polls was suspended in four of the country's 76 provinces. All four were southern provinces where the demonstrators, who are seeking to oust Prime Minister Yingluck Shinawatra, enjoy support. The events followed comments Friday by the powerful army chief in which he declined to rule out the possibility of a coup in the country, which is a major US ally, Southeast Asia's second-largest economy and a popular tourist destination. The long-running dispute between Thailand's bitterly divided political factions flared anew in November after Yingluck's elected government tried to introduce an amnesty bill for her brother, former prime minister Thaksin Shinawatra, to enable him to return to Thailand from self-imposed exile and escape a jail term for corruption. Yingluck called early elections as a way of diffusing the crisis, but the protesters are demanding she resign and hand over power to an unelected council to carry out reforms. They are trying to disrupt the polls, which most people believe will give her a strong mandate thanks to strong support in the north and northeast of the country. On Thursday, protesters tried to overrun a Bangkok sports stadium where election candidates were gathering to draw lots for their positions on ballots. Two people, including a police officer, were shot dead. The attack early Saturday took place close to a protest camp in central Bangkok, according to a government-run medical center. It said a 31-year man was killed by gunfire and two others wounded in the attack, which occurred at around 3:30 a.m. Local media said unidentified gunmen opened fire on guards close to a protest camp before escaping into the night. Hundreds of candidates Saturday were registering for the polls, but the process was stopped in four southern provinces because protesters blocked the venues and local election officials wanted to avoid violence, said Puchong Nutrawong, secretary general of Thailand's election commission. Registration continued in a fifth province – Surat Thani – despite protests there, he said. “Our policy is to avoid any confrontation,” Puchong said. — AP