Shivangi Shibu was making a list of names Thursday evening of the hundreds of international students trapped in Sumy, Ukraine, when she looked out the window and saw the dark sky illuminate a bright yellow.
"Then we heard a loud sound. We just ran to bunkers," said Shibu, a fifth-year student at Sumy State University originally from Patna, India.
Five minutes later, students were unable to send text messages on their phones, and the elevator stopped working. The power had gone out.
"We thought that we would not be able to connect to world," said Shibu, 25.
When the power returned Friday, she ran through the halls screaming with joy.
Shibu is one of hundreds of students stuck in Sumy, a city in northeast Ukraine. Russian tanks rolled into the area – about 30 miles from Russia – on Feb. 24.
Since then, residents have had dwindling access to food, water and electricity. Now Shibu and fellow students are calling out to the world for help, speaking out about the situation on social media using the hashtag "savesumystudents."
"If we're not evacuated in a day two, I don't know if we'll survive or not," one Indian student, Jakaria Hussain, wrote on Twitter.
"Evacuate us before our lives are merely reduced to bodies," another student, Mahek Shaikh, wrote.
Third-year student Shivangini Bhattacharyya wrote: "Everyday we wake up with a hope that help is coming our way, only for it to be crushed down into pieces."
Shibu said the students were caught off guard by the invasion.
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"It was very sudden. Advisory was given to us that we should evacuate on the 22nd that students should leave the place," she said. "Attack started on the 24th. So it was very unpredictable."
Samuel Olaniyan, a fourth-year student from Nigeria, said the students rented a bus in an attempt to leave the city but were shot at by Russian soldiers. Olaniyan said soldiers positioned outside the hostels to prevent the students from leaving.
"We just want to go home," said fourth-year student Precious Olawale. "We’re not asking for much. We’ll literally go with just the clothes on our back if it’s possible."
There are about 700 Indian students and 400 Nigerian students in the city, along with a handful of students from Turkey, South Africa, Tanzania and elsewhere, the students said. There are six hostels for students in the university complex, she said. Most students are studying medicine, but a few study other subjects.
"We have someone from every place in the world, and we still can't get out," Olawale said.
The students gathered as much food as they could before the war began but are now out of food and water, several said.
"We are in a rush, gather food, make food to survive," she said. "Some locals are helping, but we're not getting proper food. Sometimes we get potatoes from some persons. Sometimes we get carrots."
Shibu said the students are gathering water by melting snow and catching water runnoff from the roof in any empty vessels they can find – used bottles, buckets, tubs. On Friday, the students received two 20L water bottles from locals, she said.
"When it comes to evening, there is darkness. We cannot turn on lights because of curfew," Shibu said. "We have to burn candles or use phone lights just when we have emergency walks to the toilets or other rooms. So it's dark."
The students said they wake up most mornings to the sound of explosions and spend about 20 hours a day in the bomb shelters beneath the hostels.
One explosion woke the students up at 5:30 a.m. Saturday morning, Olawale said, sending them running downstairs. "Sometimes the explosions will shake our windows," Olawale said.
Olaniyan said the days "have no semblance of structure."
"We don’t know if today would be our last," Olaniyan said. "I try to have my bath as infrequently as possible. No one wants to be stuck in the bathroom during an air strike."
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None of the students are injured, but some are falling sick, Shibu said. The heating system in the buildings has broken, so students are sharing portable heaters, she said.
"It's very, very hard to handle," she said. "I'm mentally exhausted. When the bombs and gunfire shots were coming continuously, it was very hard to cope with. I was even hallucinating, thinking like where am I? It was very hard."
The students said they have heard from Indian and Nigerian government officials who said they were trying to assist with an evacuation.
"Nothing seems to be bearing fruit," Olawale said. "They keep telling us they need a ceasefire to get us all out."
The Indian embassy in Moscow and the Nigerian ministry of foreign affairs did not immediately respond to requests for comment.
"We need peace because things can be resolved on tables too instead of on the ground," Shibu said. "We don't want to be casualties. No one wants to become casualties. And no one should be punished for unreasonable things."
Shibu spoke to USA TODAY around midnight Friday. She said most other students had gone to bed, but she was unable to sleep.
"Sumy is my second home. Ukraine is my second home. We feel bad for all the people we know, all the persons we are connected to," she said. "Even if I will go back, it will haunt me."
