The Thai navy has denied reports that its personnel opened fire on a group of Rohingya refugees, killing at least two.
Thai Navy commander Admiral Surasak Rounroengrom said that "no [Thai] navy officer could be that ruthless".
He was responding to reports that Thai sailors shot at a boat of around 20 Rohingya refugees off Thailand's south-western coast in February.
Thousands of Rohingyas are fleeing ethnic violence in western Burma.
Many of the boats, often bound for Malaysia, end up on Thailand's west coast.
Eyewitnesses told journalists and human rights groups that they saw several bodies in the water, and had sheltered some refugees who escaped after the incident.
"Navy personnel fired into the air three times and told us not to move," a refugee told Human Rights Watch (HRW). "But we were panicking and jumped off the boat, and then they opened fire at us in the water".
Adm Surasak said that navy officers had no reason to kill Rohingya refugees, because they were not an enemy.
"Since the policy is to push them back out to sea, we provide humanitarian aid with food and water, medicine and gas for them to continue their journey. All we do is help them, even fixing their boats [if necessary], before sending them back on their way," he said.
In the past, Thai authorities have been accused of dragging refugee boats that end up in Thai waters out to sea, leaving them to die. They have also been accused of selling on asylum seekers to human traffickers.
While the government has promised an investigation into the incident, Thai officials are rarely called to account over these kinds of allegations, the BBC's South East Asia correspondent Jonathan Head reports.