Indian students in Kharkiv complained of great difficulty in leaving the city.
Ukrainian forces are keeping a large group of Indian students as "hostages" in Kharkiv, the Russian Defence Ministry has alleged, amid an escalating assault on the country on Wednesday.
"According to our information, Ukrainian authorities are forcibly keeping a large group of Indian students in Kharkiv who wish to leave Ukrainian territory and go to Belgorod," a Russian military spokesperson said at a briefing.
"In fact, they are being held as hostages... Russian armed forces are ready to take all necessary measures for the safe evacuation of the Indian citizens. And send them home from the Russian territory with its own military transport planes or Indian planes, as the Indian side proposed to do," he added.
The startling claim by the Russians came not long after Prime Minister Narendra Modi spoke to Russian President Vladimir Putin and discussed the situation in the eastern Ukrainian city of Kharkiv, where over a thousand Indian students were said to be stranded.
Kharkiv is virtually under Russian control and the girl students have already been sent on their way to Ukraine's western border by train -- a 20-hour journey -- with the help of Russians, government sources told NDTV.
Efforts are on to evacuate the boys also, sources said shortly before the 6 pm deadline was about to expire.
Earlier in the day, first-hand accounts of students stranded at the railway station gave a glimpse into their desperate situation as the Indian government issued an urgent all-caps appeal to its citizens to immediately leave Ukraine's second-largest city.
Students complained of being kicked, intimidated and not being let on trains leaving the city, prompting many to start walking towards one of the three locations specified by the Indian government between 11 and 16 km away.
Located in the eastern part of the city close to the Russian border, Kharkiv has been facing intense attacks since the invasion started and they have intensified over the past two days. At least two Indian students have died since the conflict began - one in Russian shelling and another in a hospital while being treated for an illness.