BANGKOK—A rights group is urging Thailand to investigate an alleged shooting by Thai sailors that killed at least two Rohingya last month.

Human Rights Watch said Wednesday its investigation showed Thai sailors opened fire at a group of asylum seekers off the coast of Phang Nga province.

It called for Thai authorities to prosecute officers, including those who gave orders to fire, if excessive force was used.

Prime Minister Yingluck Shinawatra told foreign journalists on Monday the government do not encourage violence and will investigate the matter. She didn't give details.

Rohingya Muslims face discrimination in Buddhist-majority Myanmar, and tens of thousands of them flee by boat each year to seek asylum in other countries.