Myanmar authorities detained 173 ethnic Rohingya aboard a boat off the southern coast, authorities said on Tuesday, amid signs that more members of the Muslim minority group are making perilous sea voyages to escape persecution.

The navy seized the vessel carrying the group, including 22 children, in Tanintharyi Division's Kawthaung township on Sunday, said military spokesman Tun Tun Nyi.

"Our navy found them on a suspicious boat in the sea," he told Reuters by phone. "The police will proceed according to the law."