Last Updated Sep 20, 2015 9:49 AM EDT
VIENNA, Austria - Austrian officials said Sunday that 11,000 migrants crossed into the country from Hungary in the 24-hour period that ended on midnight Saturday, as European governments rush to cope with the huge number of people moving across Europe.
The country's interior ministry said that another 7,000 are expected Sunday at the main Nickelsdorf crossing, east of Vienna.
Ministry officials are meeting with charity organizations to try and find temporary shelter for the new arrivals, who are fleeing conflict and poverty in the Middle East, Africa and Asia.
After the announcements, German federal police said they are expecting two special trains from Austria to bring migrants across the border into Germany via the southeastern town of Freilassing.
The trains will be carrying some 500 migrants each and are expected to arrive Sunday evening. Another five special trains with 500 people each on board will arrive in Freilassing from Austria on Monday.
Meanwhile, coast guard officials said 13 migrants have died after their boat collided with a ferry off the Turkish coast.
Turkey's coast guard agency said in a statement to its website that it intervened after being alerted that a commercial vessel hit a migrant boat off the western port city of Canakkale and that bodies were in the water.
An official at the agency says that eight people had been rescued following Sunday's incident. He said search-and-rescue operations were ongoing.
Further details about the crash were not immediately available.
Hungary has reopened its main border crossing with Serbia after sealing it off five days earlier to prevent migrants from entering its territory.
Hungarian Interior Minister Sandor Pinter said the crossing on the M5 highway between Roszke, Hungary, and Horgos, Serbia, was reopened Sunday for vehicles, which will be checked.
The crossing was the site of clashes on Wednesday between baton-wielding Hungarian riot police and migrants and the reopening follows negotiations with Pinter's Serbian counterpart, Nebojsa Stefanovic.
Relations between Hungary and Serbia have been complicated by Hungary's decision to construct a razor-wire fence along its 110-mile border with Serbia to keep migrants out.
Pinter indicated that some of those tensions were easing, saying: "We determined how to handle this extraordinary situation together and tried to find a joint solution."
The border closure had hampered trade in the region.
While Hungary has repelled migrants at its southern border with Serbia with a razor-wire fence, those arriving from Croatia on its western border are instead greeted with buses and trains that escort them to Austria.
Hungarian Foreign Minister Peter Szijjarto told news portal index.hu on Sunday that migrants entering from Croatia are receiving the favorable treatment for now because Hungary doesn't yet have a fence completed along its frontier with Croatia, whereas the fence with Serbia is complete.
Szijjarto explained that without a fence, expelling migrants back into Croatia would create chaos.
The result is that more than 16,000 migrants have crossed into Hungary from Croatia since Friday, whereas the Serb side of the border has been all but emptied of migrants.
It is not clear when the fence with Croatia will be completed.
After lashing out against Croatian officials, Hungarian Foreign Minister Peter Szijjarto is now trading barbs with his Romanian counterpart over a razor-wire border fence that Hungary is building between the two countries to keep out migrants.
Hungary's erection of fences is deeply straining its ties with neighboring countries, who feel the problem of the huge flow of migrants is being unfairly pushed onto them. After completing a fence along the border with Serbia, Hungary is now building fences along its borders with Croatia and Romania.
Romanian Foreign Minister Bogdan Aurescu on Saturday called the border closure an "autistic and unacceptable act" that violated the spirit of the European Union.
On Sunday, Szijjarto said, "We would expect more modesty from a foreign minister whose prime minister is currently facing trial." That was a reference to corruption charges filed recently against Romanian Prime Minister Victor Ponta.
Szijjarto added: "We are a state that is more than 1,000 years old that throughout its history has had to defend not only itself, but Europe as well many times. That's the way it's going to be now, whether the Romanian foreign minister likes it or not."
The Hungarian Foreign Ministry has called in the Romanian ambassador for a consultation on Monday.
A boat with 46 migrants or refugees has sunk in Greece and the coast guard says it is searching for 26 missing off the eastern Aegean island of Lesbos.
The coast guard says a Lithuanian helicopter from the European border patrol agency Frontex spotted people in the sea off the southeastern coast of Lesbos early Sunday.
Two coast guard vessels headed to the area and have rescued 20 people. The survivors say there were a total of 46 people on board.
No information is immediately available on their nationalities.
Hundreds of thousands of asylum seekers, mostly Syrians and Afghans fleeing conflict at home, have arrived in Greece from the nearby Turkish coast so far this year.