 Image copyright Reuters Image caption Migrants are crossing into Croatia where they are being registered 
 
 The first group of migrants has reached Croatia - opening up a new route to northern EU countries, a day after Hungary sealed its border with Serbia. Already, the migrant trail was adapting, finding new ways to reach western Europe. More on the migrant crisis: 
 
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 Crisis explained in graphics 
 
 The BBC's Lyse Doucet says buses, vans and cars have been taking migrants away from the Serbia-Hungary border area towards the Serbian capital, Belgrade, and the border with Croatia. Serbian alarm over stranded migrants 
 
 Hungary has also said it could extend its fence to the border with Romania - a possible new route. Analysis: BBC's Guy Delauney, Belgrade 
 
 All year, Serbia has taken a relaxed attitude towards the migrants and refugees entering from neighbouring Macedonia. But it was only Croatia’s first day at the leading edge of the mass migration, and authorities were scrambling to coordinate their response with E.U. Serbian media say at least 10 buses were heading to the town of Sid, near the Croatian border, from Presevo near Serbia's southern border with Macedonia. Croatia's Prime Minister Zoran Milanovic told parliament that authorities were "entirely ready to receive or direct those people where they want to go, which is obviously Germany or Scandinavian countries".
– More than 500 migrants have been detained for illegally entering Hungary or breaching a border fence, with nearly 50 criminal cases on the books since new laws took effect yesterday, the New York Times reports, while the BBC notes that Hungarian riot police today fired tear gas at migrants trying to break through the border with Serbia. And as restrictions tighten, migrants are seeking other ways into Western Europe through Slovenia and Croatia, as well as through Hungary's border with Romania. Issues remain: Hungary’s poorer neighbors may be ill-equipped to handle the flow, and there are areas peppered with land mines, remnants of the Balkan Wars. While solutions are sought, thousands spent last night in a Vienna train station, per the Times, while at least 22 migrants drowned yesterday in the Aegean Sea, the Post notes—a sad repeat of a similar incident a couple of days earlier. Leaders of neighboring nations are scrambling to come up with their own plans for dealing with the influx, which is no small task: The EU border agency notes a head count of 500,000 migrants at EU nations' entry points so far in 2015; last year that number was around 280,000, the BBC reports. Many are refugees fleeing high-conflict areas such as Syria and Iraq, per the Washington Post, which adds there's a noted "absence of a coordinated policy for the unprecedented influx." "Barbed wire in Europe in the 21st century is not an answer, it's a threat," Croatia's PM says, per the Post, adding that Croatia would "accept and direct" migrants through his country. An Egyptian billionaire who says he wants "to clear my conscience as a human being" has come up with an even more creative stopgap for the Syrian refugees involved: hosting them on two available Greek islands, using a joint-stock company to accept donations, Bloomberg reports. (The US is trying to help out.)