The bodies of 13 Rohingya men were reportedly found dumped by a roadside in Hlegu Township, Yangon, on Monday morning.
Their wet bodies were left near a road linking Highway 7 and Ngwe Nanthar village and taken to Yangon General Hospital for a post-mortem, said the regime.
Rohingya rights activist U Nay San Lwin wrote on social media that the bodies showed signs of beating. The Irrawaddy could not independently verify his comments.
Risking prosecution on immigration charges with potential imprisonment, Rohingya in Rakhine State continue to leave to find work, driven by poverty and institutionalized discrimination.
They often cross illegally into Thailand and try to reach Malaysia.
On November 28, 68 Rohingya, including women and children, were also arrested in Hlegu.
The detainees were identified as Rohingya from Buthidaung Township in Rakhine State, the media reported, quoting Hlegu police.
At least 10 Rohingyas heading to Yangon were arrested by the regime on the Yangon-Mandalay highway in October.