While officials did not link the two incidents directly, the violence came weeks after the government reopened a dialogue with insurgents from a Malay-Muslim minority in the southern part of the Buddhist-majority country.
The siege took place in Narathiwat province, where a combined force of soldiers and police surrounded a house in the Ra-ngae district on Friday following a tip-off that suspects linked to bomb attacks last year were hiding inside.
Authorities said they tried to negotiate with the suspects, before finally raiding the house.
One volunteer ranger was hurt and the two suspects killed in the raid.
Separately, one person was injured when at least 13 small explosions struck the town of Yala late on Friday, mostly on roadsides in front of convenience stores, shops, a market, an animal hospital and a car repair shop, deputy police spokesman Kissana Phathanacharoen said.
On Saturday police found at least three bombs that had not exploded, made from spray cans and metal pipes with timers attached.
Kissana said police suspect the explosions were aimed at causing a disturbance more than damage or injuries.
As with most attacks in Thailand's deep south, there was no claim of responsibility.
The main rebel group in the region, Barisan Revolusi Nasional, did not immediately reply to a Reuters request for comment.
More than 7300 people have died since 2004 in a separatist insurgency in Thailand's largely ethnic Malay provinces of Yala, Pattani and Narathiwat, according to the Deep South Watch group which monitors the violence.
Rebel groups have called for independence for these provinces bordering Malaysia, which were part of a sultanate called Patani annexed by Thailand in 1909 as part of a treaty with Britain.
The Thai government has restarted a peace dialogue with the main insurgent group after a two-year break of talks due to the COVID-19 pandemic.
