Migrant trail: Volunteers at Serbia-Croatia crossing

Slovenia has threatened to erect a fence along its border with Croatia if an EU plan agreed on Sunday is not implemented.

Some 85,000 refugees have poured into the tiny nation in the last 10 days, after Hungary closed its Croatia border.

The BBC's James Reynolds reports from Berkasovo, the border crossing between Serbia and Croatia, which he describes as one of the most organised crossings in the migrant trail.