Eight soldiers were killed by a roadside bomb in the restive Thai south early Saturday morning, an army spokesman said.
Another four people -- two soldiers and two civilians -- were wounded in the blast in Krongpinang district of the Muslim-majority Yala province.
The soldiers had been on duty all night at their base and were returning to their residence in a military truck when the roadside bomb went off.
"It was a very powerful bomb that completely destroyed the truck," Colonel Pramote Promin told AFP by phone.
"Ten soldiers were in the truck. Eight died and two were wounded," he said, adding that two villagers had also been injured in the blast.
There was no immediate claim of responsibility, but rebel groups have carried out similar attacks in the past.
A nine-year-old insurgency has claimed more than 5,500 lives in the Muslim-dominated south, where many local people complain of a long history of discrimination by Thai authorities in the Buddhist-majority nation.
Security personnel and those connected with the government are regularly targeted in the attacks, as well as Muslims perceived to be collaborating with the authorities.
Thailand held its first official talks with representatives of one of the main rebel groups, the Barisan Revolusi Nasional (BRN), earlier this year, but failed to reach an agreement and the daily violence continues.
Two Muslim men, including a village headman, were shot dead in Narathiwat province in separate incidents on Friday afternoon, the police said in their daily update.