Indian students in Ukraine who spent days stranded at the Polish border have told of “19th-century racism” as they watched Ukrainians’ pets allowed to cross before they were.

“It all comes down to black and white,” said medical student Muhammad, speaking from a hostel in Lviv on Tuesday. “They are Europeans and we are just Indians.”

Muhammad, originally from New Delhi, said he and hundreds of other foreign students had been denied access to the Polish border and forced to return to the city, 40 miles away, a few days earlier.

“What we suffered in the last three days was the worst thing that I’ve ever experienced,” said his classmate Jayesh.

“We were scared for our lives,” added Muhammad.

The two medical students were forced to spend three nights in freezing temperatures at a checkpoint close to the Polish border. Temperatures dropped as low as -6°C and there was no food, water or shelter from the snow.

“We collected wood from the nearby forest and started a fire just to survive. Some students started to get hypothermia and had to be taken to hospital,” Muhammad told openDemocracy.

In the past week, African, Asian and Caribbean people, many of whom are students, have shared reports and footage of themselves being prevented from leaving the country. Some told openDemocracy they had witnessed students being assaulted and others left needing emergency treatment for hypothermia after being barred for days from crossing borders.

Muhammad, 23, and Jayesh, 21, are two of the 18,000 Indian students who were stranded in Ukraine when Russian troops invaded last week. When their flights were cancelled, they tried to make their way out through a land border.

On Friday, they took a taxi from Lviv with a group of students from the city's National Medical University to the village of Shehyni, where there is a border crossing to Poland. They were stopped at a checkpoint by Ukrainian guards about four miles from the border.

At the checkpoint, Muhammed found there were hundreds of foreign students stuck there, some also from India, as well as others from Pakistan, Nepal and several African countries. They were separated from Ukrainians, who, Muhammed said, were the only people being let through.

“The Ukrainians were going through with their dogs and cats. Even they were treated better than the Indian students,” he said.

The pair said checkpoint guards became violent when attempting to control the crowd, pushing people back and pointing guns at students. “When one woman fell to the ground, a guard dragged her by hair,” said Jayesh, who is from Mumbai.

A video they recorded of the incident, which was later shared by Indian MP Rahul Ghani on Twitter, shows people in high-vis who Muhammad identified as border guards firing warning shots into the air and dragging people away from the entrance of a fenced-off checkpoint (see above).

Muhammad and Jayesh, who spent the last three years studying for a medical degree, said they were shocked by what they had experienced at the border. “We’ve never felt anything like that. I thought the racism that we saw there, the treatment of Indian people, was like we were living in the 19th century,” said Muhammad.

On Wednesday, Muhammad said he had managed to cross the border to Romania and had been provided shelter and food by the government. Indian embassy officials told him that an airlift was being arranged for students in Romania.

According to the Ukrainian government, there are 76,548 international students from 155 nations enrolled at the country’s universities. The largest group, accounting for almost a quarter of the foreign student population, are Indian nationals. They are followed by Moroccans, Turkmenistanis, Azerbaijanis and Nigerians.

In the past week, hundreds of Nigerian students have crossed over the border to Poland but many more remain stranded in Ukraine.

Tade Daniel Omotosho, who is chair of the Nigerians in Diaspora Organisation Poland, said he had received hundreds of calls from desperate students needing support. Some said they had also experienced racial discrimination while trying to make their way out of the country.

“I heard people tell me that they were asked to get off trains, of people complaining of being sick and not being attended to, of people saying that they delayed me for no reason. I’ve heard people saying that ‘they kept me in a confined room,’” said Omotosho.

In the last week, several videos have circulated on social media appearing to show Africans being denied entry onto trains or through borders, prompting condemnation from the Nigerian government.

On Monday, Nigeria’s special adviser to the president on diaspora affairs, Abike Dabiri-Erewa, said: “Africans are being denied entry through the Ukrainian borders. The minister of foreign affairs, Geoffrey Onyeama, has taken this up with the Ukrainian ambassador. Our people who want to leave must be allowed to.”

Omotosho said that he understood that Ukrainian officials had been prioritising women and children at train stations, but had heard reports from students that Nigerian women had been segregated from Ukrainian women too.

“That spells it out clearly that there is some discrimination. So it’s not just about letting women and children go first – it seems obvious that there is some form of segregation and it shouldn't be tolerated,” he said.

“That shouldn't happen because we’ve all got solidarity for Ukraine now.”

On Monday, a statement by the Ministry of Foreign Affairs of Ukraine dismissed reports of discrimination towards foreign students as “Russian disinformation”.

“There is no discrimination based on the race or nationality, including when it comes to the crossing of the state border by foreign citizens,” it said.

But the United Nations said at a press conference on Tuesday it was aware that some non-European refugees had faced discrimination.

Filippo Grandi, the organisation’s high commissioner for refugees, said: “You have seen reports in the media that there are different treatments – with Ukrainians and non-Ukrainians. Now our observations, and we possibly cannot observe every single post yet – but our observations [are] that these are not state policies – but there are instances [in] which it has happened.

“There has been a different treatment […]. There should be absolutely no discrimination between Ukrainians and non-Ukrainians, Europeans and non-Europeans. Everyone is fleeing from the same risks,” he added.