An estimated 18,000 Muslim Rohingya from Myanmar have crossed over to Bangladesh in the last seven days, according to the International Organization of Migration. Fighting began between the military and an armed Rohingya group last Friday. Hundreds of desperate families are now trapped in a no man's land between the two countries. And the UN says that the number of people who need help will rise in the coming days. Al Jazeera's Florence Looi explains. Subscribe to our channel: http://aje.io/AJSubscribe Follow us on Twitter: / ajenglish Find us on Facebook: / aljazeera Check our website: http://www.aljazeera.com/