Refugees from Ukraine, including dozens of children and two women with their cats, camped overnight at a train station in neighbouring Poland after fleeing Russia's invasion on Thursday.

"I come from Kyiv. I heard the explosions next to my building... and I quickly packed, I took almost everything with me," said Olha, a 36-year-old teacher at the Kyiv Polytechnic Institute, who gave only her first name.

Hours after fleeing the fighting in her homeland, she was among around 200 arrivals bedding down at the station in the town of Przemysl in southeast Poland, just a few kilometres from the Ukrainian border.

Mostly women, they filled almost every seat in the halls or huddled on yellow camping stretchers alongside their suitcases, many anxiously scrolling the news from the frontline on their phones.

Ukrainians at the Dorohusk border crossing between Poland and Ukraine
Ukrainians at the Dorohusk border crossing between Poland and Ukraine AFP / JANEK SKARZYNSKI

"I feel safe here but I cannot really help my relatives and friends. Many of them are in danger and cannot leave as quickly," said Olha, who planned to travel to join her boyfriend in Switzerland.

"There's a lot of struggle ahead of us," she told AFP, adding, "Ukraine is not Russia."

Polish officials of all stripes, including police and army personnel, were present as troops served up free soup.

Those sheltering in the station were also given "paczki" doughnuts -- a tradition during the Christian Fat Thursday holiday in Poland.

Preperations are underway at the reception centre for refugees from Ukraine established in Dorohusk
Preperations are underway at the reception centre for refugees from Ukraine established in Dorohusk AFP / JANEK SKARZYNSKI

Other officials were registering people at a table and helping them book tickets onward.

Konstantin, pacing back and forth, said the bombings and other "very scary things" prompted him to quit his homeland.

"I only saw videos and messages from friends and that made me leave. I'm going to a friend in Germany and then I'll see what happens," he told AFP.

"I don't know when I will return to Ukraine because I think it's huge trouble for Ukraine and it could take months, years maybe," added the 25-year-old, who declined to give his full name.

Ukrainian business owner Iryna called Russia's invasion of her country "an action against humanity."

Asked how long she thought the war would last, she said it was hard to say but that "I would of course like the global leaders to make a deal and for this to be over soon."

"However, I think that Ukraine cannot agree to peace on Russia's terms. Definitely not.

She added: "Ukraine is an independent nation which cannot subjugate itself to Russia".