GENEVA (AP) — The U.N. refugee agency said Monday that more than 500,000 people have fled Ukraine since Russia invaded the country last week.

U.N. High Commissioner for Refugees Filippo Grandi gave the estimate in a tweet.

The latest and still growing count had 281,000 people entering Poland, more than 84,500 in Hungary, about 36,400 in Moldova, over 32,500 in Romania and about 30,000 in Slovakia, UNHCR spokeswoman Shabia Mantoo said.

The rest were scattered in unidentified other countries, she said.

Another train carrying hundreds of refugees from Ukraine arrived early Monday in the town of Przemysl in southeastern Poland.

In winter coats to protect them against near-freezing temperatures, with small suitcases, they lined up at the platform to the exit. Some waved at the cameras to show they felt relief to be out of the war zone. Many were making phone calls.

The welcome that Poland and Hungary are showing Ukrainians now is very different from the unwelcoming stance they have had toward refugees and migrants from the Middle East and Africa in recent years. Hungary built a wall to keep them out when a million people, many Syrians fleeing war, arrived in Europe in 2015.

Poland is now building its own wall with Belarus after thousands of mostly Middle Eastern migrants sought to enter from Belarus in past months. The EU accused Russia-backed Belarus of encouraging that migration surge to destabilize the EU. Some of those people denied entry into Poland died in forests.

But Ukrainians are viewed very differently by Poles and others because they are mostly Christian, and, for the Poles, fellow Slavs with similar linguistic and cultural roots.

Transcarpathia, Ukraine’s westernmost region which borders Hungary, is also home to about 150,000 ethnic Hungarians, many of whom are also Hungarian citizens. While Russia’s invasion has not yet extended to that area, which is separated from the rest of Ukraine by the Carpathian Mountains, many have decided not to wait for the situation to get worse.