Police in Bangladesh are ignoring government orders to prevent people fleeing violence in neighbouring Myanmar from crossing the border.
A BBC correspondent in Cox’s Bazaar, Bangladesh, says members of Myanmar’s minority Rohingya Muslim community are streaming through crossings, without being stopped.
The UN now estimates that 58,000 refugees have made it across.
Violence erupted in Myanmar’s Rakhine state just over a week ago.
Refugees accuse the Myanmar security forces and Buddhist mobs of burning their villages.
The Myanmar government says their security forces are responding to an attack last month on more than 20 police posts by Rohingya militants.
Subsequent clashes have sent civilians from all communities fleeing.