Bosnia should do more to organise shelter for migrants before the arrival of winter, including for hundreds sleeping rough in towns near the Croatian border, Reuters reported citing the U.N.

“The key challenge now is how to prepare for winter,” said Stephanie Woldenberg, a senior protection officer for the UNHCR refugee agency. “It is the race against time and UNHCR is particularly concerned about vulnerable families and individuals who are most at risk.”

Bosnia’s Security Minister Dragan Mektic addressed a press conference in Banja Luka on Sunday, saying that the exact number of migrants heading to Western European countries whose entry into Bosnia was registered is 14,969, of which 13,958 expressed an intention to seek asylum, but only 399 actually did that.

Speaking at an event sponsored by the Organisation for Security and Cooperation in Europe (OSCE), she said more than 1,000 refugees and migrants were sleeping in the open in Bihac and Velika Kladusa, two towns in the northwestern Bosnia near the Croatian border.

Several thousand migrants remain in Bosnia after Croatia tightened its borders and new people arrive daily, crossing illegally from Serbia.

Bosnia state authorities’ attempts at refurbishing inadequate facilities where migrants are currently accommodated have been slow because of a lack of funding and cooperation from local counterparts, Reuters said.

Woldenberg said a priority for the authorities was to protect families with children, single women and unaccompanied minors.

“Safe appropriate accommodation must be provided for these groups as a priority,” she said.