DHAKA (Reuters) - Police in Bangladesh killed seven members of a gang of armed robbers on Monday during a raid on their hideout on a hillside overlooking a camp for Rohingya refugees in the southeast of the country, a police spokesman said.

Crime and violence are on the rise in the squalid, sprawling camps around the coastal city of Cox’s Bazar, where hundreds of thousands of ethnic Rohingya took shelter in recent years after fleeing persecution in neighbouring Myanmar.

Police said the gang had been engaged in narcotics and human trafficking, and the three-hour raid was conducted by a special police unit known as the Rapid Action Battalion (RAB).

“Firearms and a large amount of ammunition have been recovered from the spot,” said Sujoy Sarkar, a spokesman for the RAB. He said officers came under fire as they launched the raid, but suffered no casualties. Rights groups have accused Bangladesh police of carrying out extrajudicial killings.

At least 50 Rohingya people have been killed in shootouts in Bangladesh since the latest mass influx of Rohingya refugees in August 2017, according to police.

Scores of Rohingya have boarded boats in recent months to try to reach Malaysia and Thailand, prompting fears of a fresh wave of people-smuggling by sea.

Authorities have begun erecting barbed-wire fences around the camps in a bid to tackle crime, while a plan to relocate refugees to a flood-prone island has been put on hold.