Bangladeshi border guards have destroyed around 20 boats that were used to ferry Rohingya Muslims fleeing Myanmar, Reuters reported on Thursday.

Lieutenant Colonel Ariful Islam, the local commander of the border guards said they were cracking down on human trafficking and the smuggling of the drug called methamphetamine. “The boats are trying to carry passengers they are not supposed to,” he was quoted as saying.

Some refugees claimed the border guards also beat up and arrested passengers who disembarked in Bangladesh’s southern area of Shah Porir Dwip, before destroying the boats.

Refugees like Ibrahim Holil and Farous Ahmad from Myanmar said that they were beaten despite there being nothing prohibited in their boats. Ahmad said that his sons, who had worked as crew on the boats, were also arrested. “People told me the border guards would shelter us in Bangladesh but yet they arrested them [my sons] and we had to spend the whole night sitting,” Ahmad said.

Islam, however, denied these reports. He said that the organisers of these boat journeys were exploiting Rohingyas by charging them. While some passengers said that they had paid a lot of money for the trip, others said it was free.

More than 5 lakh Rohingyas have fled to Bangladesh since August 25. Hundreds have died since Rohingya militants targeted 30 police sites at an army base in a coordinated strike, according to the United Nations. The UN described the violence against the Rohingyas as an “ethnic cleansing”. Rohingyas have been denied citizenship in Myanmar and are classified as illegal immigrants. The community has been subjected to violence by the Buddhist majority and the Army in Myanmar, though the country has repeatedly denied this claim.