BANGKOK  Stateless refugees from Myanmar are suffering beatings and deportation in Bangladesh, according to aid workers and rights groups who say thousands are crowding into a squalid camp where they face starvation and disease.

In a campaign that seems to have accelerated since October, the groups say, ethnic Rohingya refugees who have been living for years in Bangladesh are being seized, beaten and forced back to Myanmar, which they had left to escape persecution and abuse and which does not want them.

“Over the last few months we have treated victims of violence, people who claim to have been beaten by the police, claim to have been beaten by members of the host population, by people they’ve been living next to for many years,” said Paul Critchley, who runs the Bangladesh program for the aid group Médecins Sans Frontières, also known as Doctors Without Borders.

“We have treated patients for beatings, for machete wounds and for rape,” he said, quoting a report issued Thursday that describes the situation as a humanitarian crisis. Some had escaped after being forced into a river that forms the border with Myanmar, formerly Burma. “This is continuing today.”